PM encouraged to deliver Brexit promises on election campaign visit
Boris Johnson was given the advice while knocking on doors in Mansfield.
Boris Johnson has been told to deliver on his Brexit promises or face receiving an unpleasant letter.
The Prime Minister knocked on doors in Mansfield in a bid to boost the election cause of Tory candidate Ben Bradley, who won the seat from Labour in 2017 by a majority of 1,057.
They received a positive response from the four houses they visited in Millersdale Avenue, although one resident sought assurances over the Brexit deal on offer.
Susan Kitchen, 71, answered at the third house and held her dog Peggy while speaking to the PM about the UK’s withdrawal from the EU.
She said afterwards her heart was going “ten to the dozen” and she was “absolutely shocked” to see Mr Johnson.
She told the PA news agency: “I told him I was worried about the deal he was making and asked him specifically if their laws could overrule our laws because that’s what I’ve heard.
“He said no, absolutely not, so I says to him if you’re wrong I’m going to write you a letter – and it won’t be pleasant.”
At the first house, Lucy Camm met the PM outside before he could reach the door and took a photo with him.
She said: “Jesus Christ, I cannot believe you are outside my mum and dad’s house. I cannot believe you’re in our street.
“You have definitely got our vote. We do not like Jeremy (Corbyn).”
Ms Camm told PA: “I just can’t believe he’s here.
“I wish I was kind of dressed a bit more appropriately and didn’t come running out in my socks, but it’s good though.”
Her mother Susan Camm, 70, also spoke with the PM.
Mr Johnson received a positive response at the second property while at the final house one man greeted Mr Johnson by saying: “It’s good to see you young man.”
Further planned Nottinghamshire visits to plant a tree, in connection with one of the party’s pledges, and to meet farmers were cancelled due to a change in the PM’s schedule.


database connection
limit duration in milliseconds [1 hour]
special key for indentify
error returned as the body of the response
custom header names
id to compare requests default: ip
max requests per 'id' default: 2500
redis key prefix default: "limit"
throw on rate limit exceeded default: false
array of ids to whitelist
Generated using TypeDoc
array of ids to blacklist


| ZotWeb | paper-conference | |
| Src Url | [[Chang]] (2020) | |
DrawmaticAR is an AI-AR app capable of creating interactive 3D animated experiences from story words written in the designated section on an AR marker (Magic Paper).
DrawmaticAR - Automagical AR Content From Written Words!
[[Siggraph]] | [[SiggraphRealTime]]
Yosun Chang AReality3D Permute.xyz
app capable of creating interactive 3D animated experiences from story words written in the designate
[[ARGoal]] | [[Previsualisation]] | [[ARPreviz]]


Strike Debt is calling for a movement-wide conversation on Debt, Privilege, and Common Struggle to be held on January 21st, Dr. Martin Luther King, Jr. day.
http://www.facebook.com/events/633545176675063/
If you are in NYC, join us Judson Memorial Church at 12pm
If you are not in NYC, or are joining after January 21st, you can use the following links to participate:
|
Dear Strike Debt Chapters and Friends,
Over the past two months, Strike Debt has raised more than $500,000 through the Rolling Jubilee fund–enough to purchase and abolish more than ten million dollars worth of defaulted medical debt. A first round of beneficiaries has just been notified that their debts have been erased, and a much larger announcement is scheduled for February of this year. This bailout of the People by the People has touched a nerve, sparking an outpouring of generosity and a nation-wide conversation about the immoral and predatory debt-system of Wall Street. A consensus is emerging that no one should have to sign their future away to a creditor for access to the basic goods of life.
Building on the phenomenal momentum of the Rolling Jubilee, Strike Debt is calling for a nation-wide visioning session entitled Debt, Privilege and Common Struggle: Where Do We Go From Here? to begin January 21st, 2013–Martin Luther King Day.
Strike Debt looks to Martin Luther King as a cultural symbol of a dream deferred–a dream not just of civic equality, but of a multiracial beloved community based on economic justice at local, national, and global scales. In his seminal 1967 speech “Where Do We Go From Here?” King named “the capitalistic system” itself as the obstacle to that dream, and called for a “restructuring of American society as a whole.”
Over the past year, Occupy Wall Street, Strike Debt, and our allies have highlighted debt as a primary mechanism of contemporary capitalist society–one that is inseparable from the history of racial inequality. A debt-financed existence has been both an alluring dream and a punishing nightmare for communities of color, who have been the hardest hit by predatory lending of all sorts from subprime mortgages to pay day loans as overall wages have stagnated and public services have been rolled back. Debt is a tie that binds the 99%, but it binds some of us more tightly than others.
Throughout the week beginning January 21st, we will conjure the legacy of King and freedom struggles from around the world by gathering in places of worship, community centers, union-halls, classrooms, art spaces, dinner tables and living rooms to push forward the conversation started by the Rolling Jubilee. Where do we go from here? How do we get there? What would a bailout look like in your community? What alternative economic models can we imagine as we build a debt-resistance movement? What can we learn from history as we envision another world based on our obligations to our friends, families, and communities rather than to the 1%?
Strike Debt NYC will host its visioning session at Judson Church in Manhattan from 12 PM to 3 PM. Friends and allies from across New York City and the Northeast are welcome, including those from the faith and labor communities. The family-friendly event will feature music, slideshows, and facilitated brainstorming sessions around themes including Movements, Targets, Cities, Cooperative Economics, Alternative Credit, and more! The event will conclude with food, drinks, and a performance by the Strike Debt Radical Children’s Theater, facilitated by the Little Red Squares Childcare Collective.
For Strike Debt chapters elsewhere in the country interested in holding similar visioning events on or around J21, we encourage you to gather with friends and allies at whatever scale you feel is appropriate to have a meaningful conversation about building a debt-resistance movement–from a gathering of friends after church, over dinner or a drink at the bar to a full-on debt-assembly. We will soon be launching a “meet up” interface on the Strike Debt website, along with a visioning session toolkit with some suggestions about how to structure your event. Please let us know about your event here<EMAIL_ADDRESS>Following the distributed events, we hope to gather report-backs from participants and consolidate them in an online document that can eventually give rise to a collective blueprint for a New Economic Vision.
In the words of MLK:
I want to say to you as I move to my conclusion, as we talk about “Where do we go from here?” that we must honestly face the fact that the movement must address itself to the question of restructuring the whole of American society. (Yes) There are forty million poor people here, and one day we must ask the question, “Why are there forty million poor people in America?” And when you begin to ask that question, you are raising a question about the economic system, about a broader distribution of wealth. When you ask that question, you begin to question the capitalistic economy. (Yes) And I’m simply saying that more and more, we’ve got to begin to ask questions about the whole society. We are called upon to help the discouraged beggars in life’s marketplace. (Yes) But one day we must come to see that an edifice which produces beggars needs restructuring. (All right) It means that questions must be raised. And you see, my friends, when you deal with this you begin to ask the question, “Who owns the oil?” (Yes) You begin to ask the question, “Who owns the iron ore?” (Yes) You begin to ask the question, “Why is it that people have to pay water bills in a world that’s two-thirds water?” (All right) These are words that must be said. (All right)
Now, don’t think you have me in a bind today. I’m not talking about communism. What I’m talking about is far beyond communism. (Yeah) My inspiration didn’t come from Karl Marx (Speak); my inspiration didn’t come from Engels; my inspiration didn’t come from Trotsky; my inspiration didn’t come from Lenin. Yes, I read Communist Manifesto and Das Kapital a long time ago (Well), and I saw that maybe Marx didn’t follow Hegel enough. (All right) He took his dialectics, but he left out his idealism and his spiritualism. And he went over to a German philosopher by the name of Feuerbach, and took his materialism and made it into a system that he called “dialectical materialism.” (Speak) I have to reject that.
What I’m saying to you this morning is communism forgets that life is individual. (Yes) Capitalism forgets that life is social. (Yes, Go ahead) And the kingdom of brotherhood is found neither in the thesis of communism nor the antithesis of capitalism, but in a higher synthesis. (Speak) [applause] It is found in a higher synthesis (Come on) that combines the truths of both. (Yes) Now, when I say questioning the whole society, it means ultimately coming to see that the problem of racism, the problem of economic exploitation, and the problem of war are all tied together. (All right) These are the triple evils that are interrelated.
In other words, “Your whole structure (Yes) must be changed.” [applause] A nation that will keep people in slavery for 244 years will “thingify” them and make them things. (Speak) And therefore, they will exploit them and poor people generally economically. (Yes) And a nation that will exploit economically will have to have foreign investments and everything else, and it will have to use its military might to protect them. All of these problems are tied together. (Yes) [applause]


Background information
- The deadline for the project is Monday 25 Sept, 14:00.
- The projects (three in all) will count 20% of the final mark.
- The project work is required to be admitted to the exam.
- In order to pass this project a reasonable attempt must be made to solve all problems.
- The project should be done in groups of two or three persons. You can sign up as a group in Blackboard.
- Submit the project by uploading the project report as a pdf file to your group folder in Blackboard. Attach the code as separate files.
- Your project report should include both equations with calculations, plots and interpretation as text.
- Computer-code should be written in
Matlab
,R
orPython
. Please try to make your code readable and add comments to describe what you do. - Lectures on 18 and 22 Sept will be set aside to work on the project. You will get assistance in the lecture room 8:15-10:00.
Abstract
This project describes method for solving algorithms related to the secretary problem (aka the marriage problem, best prize problem, etc.), and a binary Markov chain. This was solved using Python. The implementation make use of basic linear algebra.Introduction
This project report was written by Eivind Baltzersen and Christer Hølestøl as an assignment to the course TMA4265 Stokastisk modellering. The intent was to solve stochastic problems numerically using computer software, and to compare the results to analytic solutions.Problem 1 : Secretary problem
Consider the secretary problem (a.k.a. marriage problem, best prize problem, etc.), where a company is going to employ a secretary among candidates for the position. Each candidate has value , and the order of the candidates is assumed to be entirely random. The company will make decisions as they go along interviewing : a candidate gets to know right after the interview whether (s)he gets the job or not. Once a candidate has been turned down (s)he can never be hired. The following strategy is run by the company:
- Interview the first candidates, and turn down every one of them.
- Set to be the highest value among the first candidates.
- Pick the first subsequent candidate with value , or the last candidate.
a)
Let denote the event that this strategy gives the best candidate. Define another event for the event that the best candidate is number in the interview process.
By conditioning on , and then marginalizing in the joint for and , show that the success probability of the strategy is
\begin{align}
P(Z = 1)
&= \sum_{i=1}^n P(Z = 1\,|\,Y = i)P(Y = i)
\\&= \sum_{i=k+1}^n \frac{k}{i-1}\frac{}{n}
\\&= \frac{k}{n}\sum_{i=k+1}^n \frac{}{i-1}
\\&\geq \frac{k}{n}\int_{k+1}^{n+1} \frac{}{i-1}\,\mathrm{d}x
\\&= \frac{k}{n}\ln\left(\frac{k}{n}\right)
\end{align}
Similarly, one may show that
\begin{equation}
P(Z = 1) \leq \frac{k}{n}\ln\left(\frac{k-1}{n-1}\right)
\end{equation}
By conditioning on , and then marginalizing in the joint for and , show that the success probability of the strategy is
b)
Compute the approximate mode of by differentiating with respect to .
Fix , and draw a plot of as a function of .
Fix , and draw a plot of as a function of .
Interpret the result.
Fix , and draw a plot of as a function of .
Fix , and draw a plot of as a function of .
Interpret the result.
c)
Fix . Draw independent realizations of values from a uniform distribution. Run the above strategy for each realization (keeping at the optimal level from b)) and use the results to answer the following:
- How many times does the strategy get the best candidate? Is the fraction similar to the analytical probability in b)?
- How often does the strategy give a candidate that is among the top three highest values?
- How often does the strategy end up interviewing all candidates?
d)
Assume the number of candidates is unknown. Now, is uniformly distributed between and . For a strategy with fixed , the probability of getting the best secretary is now
where is the uniform distribution, and is calculated in a), for fixed .
- Plot as a function of for this model. What is now the optimal ?
- Draw independent realizations of candidate number from the uniform distribution on , and values for . Run the strategy for each realization of , and answer the questions listed in c).
Problem 2 : Avalanche risk
Parts of a railroad track are at risk of snow avalanche. The avalanche risks are discretized in low (1) or high (2) classes. Low risk is more likely for low altitudes, while high risk is more likely for higher altitudes. The railroad track is split in different sections, of increasing altitude, and the risk class is modeled by a Markov chain as follows: Initial probability of low risk is and the transition probabilities are defined by .
Probability syntax
Writing mathematical syntax in Python isn't feasible, so a new syntax was created; is written asP(X = k, i = ℓ)[j]
. P()
returns a (slightly modified) namedtuple object of the state distribution at k
, and the state probabilities are accessible by either using ["key"]
or [val]
as a key, e.g. ["low"]
or [0]
. For instance would be P(X = 3, high = 4)["low"]
or P(X = 3, high = 4)[0]
. The implementation of P()
is described in
a)
Compute and plot the marginal probabilities for .
,
b)
Draw realizations of the Markov chain, and visualize the results as an image with time on the first axis and the realization number on the second axis. Compare the average results of the realizations with the marginal probabilities .
c)
One can install a sensor at location to monitor the risk. This sensor will give the perfect information about . Setting , compute and plot the following:
\begin{align}
&P\left(X_\ell = j\,\middle|\,X_k = i\right)
\\=&\,\frac{
P\left(X_k = i\,\middle|\,X_\ell = j\right)
P\left(X_\ell = j\right)
}
{
P\left(X_k = i\right)
}
\\=&\,\frac{
P\left(X_k = i\,\middle|\,X_\ell = j\right)
P\left(X_\ell = j\right)
}
{
P\left(X_k = i\,\middle|\,X_\ell = j\right)
P\left(X_\ell = j\right)
+
P\left(X_k = i\,\middle|\,X_\ell = \bar{\jmath}\right)
P\left(X_\ell = \bar{\jmath}\right)
}
\end{align}
- The forward probability for and .
- The backward probability for and .
d)
A particularly warm day in springtime snow avalanches will surely occur on the railroad line. One is worried about the cost associated with these avalanches. Assume that there are no costs at low risk locations, while each high risk location will cost kroner to clean. The expected total cost is then . One can alternatively decide to clean the tracks at all locations ahead of the daily operation, at the cost of .
The railroad company chooses the alternative with minimum expected cost, and this decision problem is mathematically formulated as follows: Based on your answer in a), what is the optimal decision?
The optimal decision is to simply clean all the tracks ahead of the daily operation, at the price of 100,000.
The railroad company chooses the alternative with minimum expected cost, and this decision problem is mathematically formulated as follows: Based on your answer in a), what is the optimal decision?
e)
By installing a sensor, as in c), one can learn about high or low risks, and this allows informed decisions about cleaning the tracks up front or not. Before conducting the measurement, a goal is to find the best location for the sensor. The expected gain in information, when the sensor is placed at location is:
Use the results from c) to compute the expected information gain. Plot the expected information gain as a function of .
What is the best location for the sensor? Discuss why this is the best?
The minimum is found at .
What is the best location for the sensor? Discuss why this is the best?


An efficient multi-core package to reconstruct an underlying network of genomic signatures of high-dimensional epistatic selection from partially observed genotype data. The phenotype that we consider is viability. The network captures the conditional dependent short- and long-range linkage disequilibrium structure of genomes and thus reveals aberrant marker-marker associations that are due to epistatic selection. We target on high-dimensional genotype data where number of variables (markers) is larger than number of sample sizes (p >> n). The computations is memory-optimized using the sparse matrix output.
| Version: | 0.0.1-1 |
| Depends: | R (≥ 3.1.0), Matrix, glasso, tmvtnorm, igraph, parallel |
| Imports: | methods |
| Published: | 2016-11-23 |
| Author: | Pariya Behrouzi, Danny Arends and Ernst C. Wit |
| Maintainer: | Pariya Behrouzi <pariya.behrouzi at gmail.com> |
| License: | GPL-3 |
| NeedsCompilation: | no |
| CRAN checks: | epistasis results |
| Reference manual: | epistasis.pdf |
| Package source: | epistasis_0.0.1-1.tar.gz |
| Windows binaries: | r-devel: epistasis_0.0.1-1.zip, r-release: epistasis_0.0.1-1.zip, r-oldrel: epistasis_0.0.1-1.zip |
| OS X binaries: | r-release: epistasis_0.0.1-1.tgz, r-oldrel: epistasis_0.0.1-1.tgz |
| Old sources: | epistasis archive |
Please use the canonical form https://CRAN.R-project.org/package=epistasis to link to this page.


The Digital City Hub For Internationals
Loading…
Hallo.City is the digital platform that offers internationals in Germany the opportunity to find the products and services in their new city in a centralized and customer-based way.
Everything you need in just a click (and in English!).
FIND
CREATE
RATE
BUY
Our Team
Maricrus Bermudex
Cofounder
Valeria Clement
Cofounder
Barbara Nino
UX/UI Designer
Ahmed Salah
Fullstack Developer
Get in Touch!
@hallocity_leipzig
<EMAIL_ADDRESS>017621442453


Delivery driver dragged from his car in Belfast hijacking
by By Press AssociationA delivery driver has been dragged from his car during a hijacking incident in North Belfast.
The man, in his 40s, was attacked while making a delivery in the Seaview Drive area on Monday night.
Two young males dragged him from his VW Golf before making off in it.
A PSNI spokesman said the man was left “badly shaken” but was not injured.
“Shortly before 10.35pm, it was reported that a man in his 40s was making a delivery in the area,” he said.
“As he returned to his VW Golf car, two young males approached the vehicle and dragged the man out of the car. It is not known in which direction the car made off following the incident.
“The driver of the vehicle was not injured but left badly shaken. The males are described as being aged in their early 20s and wearing dark, grey clothing.
“Inquiries are continuing and we are appealing to anyone who witnessed anything suspicious in the area to contact detectives on 101, quoting reference number 2078 18/11/19.”
READ MORE
Man found in burning car in Dublin believed to have been shot


box1 is parent of box2 and box2 is parent of box3
select
box1
box2
box3
hide/show
focus
local
global
translate
rotate
scale
snap translation
snap rotation
snap scale
bound translation
bound rotation
bound scale
full rotation guides
toggle euler
print rotation to console
undo
redo


marmalade signup
Email (will not be public)
Create Password
Full Name (will not be public)
Username (choose your public alias)
Favourite Colour


Your selected file was successfully uploaded to the server! Redirecting back to the file upload page in 3 seconds...


🎥 Trailerflix
This project is called, Trailerflix. It allows the user to select a movie from my
team's personal choice database and watch the movie's trailer obtained through the Youtube API. It also
provides the Rotten Tomatoes rating, and description obtained through the OMDb API. It also allows users
to save their favorite movies and display them in a separate "Favorites" page.
🌧 Weather Dashboard
This project is a weather app created using 60% Javascript. I've obtained information from the Open Weather API to display live information for select cities as well as forecasted weather for the next 5 days.
📖 Book Club
This project is called Book Club and is made up of JavaScript, Handlebars.js, and CSS. This web application allows users to view a list of books and book selections and reviews from registered users.


To install the package:
devtools::install_github("leonawicz/mapmate")
The save_map
function in the mapmate
package offers the type="network"
map type. This type of map displays networks or pathways defined by overlapping segments traversing along great circle arcs. This map type can be used to display arbitrary line segments as well if such data is provided, but the provided helper functions used here are aimed specifically at drawing great circles.
The first example uses a flat map. Therefore it is important to break lines at the international dateline when preparing the data. In the second example, lines cross the dateline are not split because the segments will be plotted on the globe.
First, begin with the network
data set provided in mapmate
is a simple data frame of lon/lat locations of various cities and corresponding weights related to population sizes. It must be expanded to a larger, more complex data frame that contains location pairs and, optionally, distances between locations in each pair. gc_endpoints
assists with this by simulating some pairs. The resulting data frame contains endpoints of lines that are defined subsequently.
library(mapmate)
library(dplyr)
set.seed(192)
data(network)
network
distFun <- function(x) 1 - x/max(x) # simple inverse distance weighting
endpoints <- gc_endpoints(network, "lon", "lat")
endpoints
Next, we sample based on a combination of weights. This is an arbitrary and optional step. The example is given primarily to make the data set used in these examples smaller in size. More importantly, the gc_arcs
helper function is used to further expand the endpoints
data frame to one containing sequences of points describing great circle arcs instead of only their endpoints.
The default number of points added between the endpoints of each great circle arc is n=50
, but this can be changed and can also differ for each arc (e.g., based on distance between points). As noted, arcs are filled out planning for use with both flat maps and a globes. A group
column is used to identify distinct arcs for plotting.
# take a weighted sample, e.g., favoring larger averaged populations and
# shorter distances
endpoints <- mutate(endpoints, Dist_wts = distFun(Dist))
endpoints <- sample_n(endpoints, 500, replace = TRUE, weight = (Pop_wts0 + Pop_wts1)/2 +
Dist_wts)
# expand data frame from endpoints to arcs, each composed of a sequence of
# points
arcs_flat <- gc_arcs(endpoints, "lon0", "lat0", "lon1", "lat1", breakAtDateLine = TRUE)
arcs_globe <- gc_arcs(endpoints, "lon0", "lat0", "lon1", "lat1")
arcs_globe
Finally, gc_paths
is used to further expand the great circle arcs data frame into one that contains sequences of ordered segments along each arc. The segments can vary in length between distinct arcs and can overlap one another within an arc. The group
argument is required to identify distinct arcs in the input data frame. size
is required to set an upper limit on the number of points constituting an arc segment; the actual length of the segments is chosen randomly and uniformly between 2 and size
. Other arguments are optional.
The direction of arc traversal can also be controlled by the direction
argument if desired. This is useful for simulations if the input data are not yet randomized or if the directions simply need to be reversed. First some setup:
n <- max(paths_flat$id)
png.args <- list(width = 600, height = 300, bg = "black")
clrs <- c("#1E90FF50", "#FFFFFF50", "#FFFFFF", "#1E90FF75")
ylm <- range(paths_flat$lat) # trimming empty southern map region
Typically, I would leave the default arguments save.plot=TRUE
and return.plot=FALSE
, but here they are reversed for the purposes of the example. This returns a list of ggplot
objects rather than saving png files. Note that I still included the png.args
argument even though width
and height
will be discarded because save_map
will take the background color specified by bg
intended for png files and use it in the ggplot2
theme applied to the returned plots.
The default background is transparent so I need to include this here since I have changed it to black. I have changed it to black in this example because I am making a reproducible gif for simplicity rather than doing any layering of separate image sequences in a video editor. Below, saveGIF
from the animation
package is used to make a simple gif from the plot sequence produced by save_map
by looping over the list of returned plots.
In summary, this is all a somewhat convoluted scenario to show you a short animated gif representing plots made by save_map
. The intended use case for save_map
is to simply export the sequence of png files and the user can do whatever they wish with those files subsequently. If literally all you want to do is make a short, simple animated gif of custom plots using a small amount of data, just use the animation package. You do not need mapmate
for that. Also, if you are using animation
in general, as with the code below, it is dependent on ImageMagick
, which you will also have to install.
gglist <- save_seq(paths_flat, id = "id", n.frames = n, ortho = FALSE, type = "network",
ylim = ylm, png.args = png.args, save.plot = FALSE, return.plot = TRUE)
library(animation)
# you may need to specify a different path on your Windows machine you may
# also need to ensure convert.exe is part of your particular installation
ani.options(convert = "C:/Progra~1/ImageMagick-7.0.6-Q16/convert.exe")
saveGIF({
for (i in seq_along(gglist)) print(gglist[[i]])
}, "network2D.gif", interval = 1/20, ani.width = 960, ani.height = 480)
This animation
-dependent example and the animated gif are not meant to be distractions from the purpose of this package. Despite the example gif, any code here related to animation
is beyond the scope of this tutorial. If you have trouble running it, see the animation
documentation and just do the following example instead, which is the way mapmate
is meant to be used:
save_seq(paths_flat, id = "id", n.frames = n, ortho = FALSE, type = "network",
file = "network2D", png.args = png.args)
# Next, do whatever you want with the files, such as import them to a video
# editing program
Here is an example plotting network paths along great circle arcs on the globe. Remember that we use the other data set, which was generated with the default breakAtDateline=FALSE
in gc_arcs
. As a side note, if you redo the above example for flat maps using the unbroken data, paths_globe
, you will see why the arc segments are handled differently when preparing data for flat maps vs. for globes.
n <- max(paths_globe$id)
png.args <- list(width = 600, height = 600, bg = "black")
clrs <- c("#FFFFFF", "#FF450050", "#FF4500", "#FFFFFF50")
gglist <- save_seq(paths_globe, id = "id", n.frames = n, col = clrs, type = "network",
pt.size = c(1, 1, 3, 2), png.args = png.args, save.plot = FALSE, return.plot = TRUE)
library(animation)
ani.options(convert = "C:/Progra~1/ImageMagick-7.0.3-Q16/convert.exe")
saveGIF({
for (i in seq_along(gglist)) print(gglist[[i]])
}, "network3D.gif", interval = 1/20, ani.width = 600, ani.height = 600)
Again, normal usage is to just do the following and then use the saved still image sequence with full user control for whatever you like:
save_seq(paths_globe, id = "id", n.frames = n, col = clrs, type = "network",
pt.size = c(1, 1, 3, 2), file = "network3D", png.args = png.args)


Author Matrix
α
Map of Medline co-authors
Each cell gives the
number of articles
shared by the corresponding
author pair


Gets a specific self-hosted runner. Anyone with admin access to the repository can use this endpoint. GitHub Apps must have the administration
permission to use this endpoint.
GET /repos/:owner/:repo/actions/runners/:runner_id
Status: 200 OK
{
"id": 23,
"name": "MBP",
"os": "macos",
"status": "online"
}


Web Components have always heavily relied on JavaScript. And that's a problem,
because they're quite opaque to search engines and social media sharing,
as they might not execute the JavaScript bits to hydrate the laconic tags that
we put in the markup. So here it comes a new proposal…
<daily-question>
<template shadowroot="open">

Question of the day

<slot></slot>
</template>

Is the cat inside?

</daily-question>
All we have to do is to define the content of the WC using the good ol' <template>
element with this new shadowroot
attribute, that takes "open" or "closed" as
values like the possible modes of .attachShadow
. So this could be done by a server!
class DailyQuestion extends HTMLElement {
constructor() {
super();
// A custom element now *might* have
// a shadow root already attached
if (!this.shadowRoot) {
this.attachShadow({ mode: 'open' });
this.shadowRoow.innerHTML = '...';
}
...
}
...
}
Now when the class gets instantiated, it might already have a shadow root defined by the DSD,
so we'd have to check its presence.
This is also retro-compatible, meaning that re-declaring a shadow root
with .attachShadow()
will just remove the one created by
the Declarative Shadow DOM, letting old Web Components still work.
<retro-banner>
<template shadowroot="open">
<link rel="stylesheet" href="/eigthies.css">

<slot></slot>

</template>
Bring the `80s back!
</retro-banner>
DSD also makes it easy (again) to load stylesheets for Web Components. All you need to do is to
insert a <link>
element inside the template, as we used to do with JavaScript.
The stylesheet gets cached too, so it won't be loaded again for all the other instances of the same
component.
Declarative Shadow DOM


When it comes to designing galleries there are a lot of ways to go when coding and developing. One is to use a HTML and CSS design to design a gallery where you see all the pictures. It would be nice with a responsive design to this as well, so it’s easier to scale down or up the design.
Here is an excellent example of what I mean:
https://www.w3schools.com/css/tryit.asp?filename=trycss_image_gallery
Another way of designing a gallery is to add a slider with images in it. A slider could be built to slide through the different pictures or slide through the margin: width (the images are with this method there all the time, but with javascript we can “show” them for the reader).
http://sachinchoolur.github.io/lightslider/ Under this link is a good example of a jQuery slider that slides through a gallery’s images.


Everyone is familiar reading a newspaper. Now if you recall a front page of a newspaper you will see rectangular boxes for each news or ad item with number columns interspersed. Now if you have to transform that on to a computer screen then you need some sort of tool to do that. Now for this purpose to first form the layout a skeleton structure of the page you use what is called HTML –(HyperText Markup Language). HTML is a computer code used to create documents on the web. This uses tags which place the text or image wherever you want to place. Tags are instructions that tell your browser what to show on a webpage. All tags start with a < and end with >. If you wish you can right click on this site and choose view page source.
Now you have the skeleton structure but you what to add color, different font types, font size, position, orientation, and so on. To do those what you use is CSS- Cascading Style sheet. The cool thing about the CSS sheet if that you can link to an external style sheet and that can change the page for you. Just by editing the one style sheet you can modify a webpage.
To have a better control on the way the webpage can be accessed to change the structure, style and content the modern way is to use DOM - Document Object Model. This is basically an interface that connects the webpages to scripts or programming language.
With the newspaper anology a paper layout is a boxes of different pictures and texts. Now each one of these box represents elements and together they can be arranged to form a page.
Each every item that needs to go on to a page can all be put in different boxes. Bascially how an individual box element appears is controlled with CSS. The CSS Box model allows to define border of a box as well as the space between the boxes.


I never thought in my life I would learn how to sew. However I did, it was not the most fun thing I have done but I made gppd gifts. I embroidered a hat with a WRA logo and I created a holiday pillow case. Backing was used to to allow the thread to pull on it instead of pulling on the hat. On our hats we used a normal backing and a waterproof one ontop of the WRA symbol so it does not break with water. The hardest part about making the pillow case was trying to sew in a straight line. I could not do that at all and at some part at the top accent piece it looks bad. I learned that a sewing machine can go at different speeds and that you control it with a pedel.


{% include header.html %}
{{ site.description | default: site.github.project_tagline }}
{% comment %} In order to hide "posts", filtered by "diplay". (Because "posts" is included in "site.collections" by default.){% endcomment %} {% assign display_collections = site.collections | where: "top-page", true %} {% for collection in display_collections %}


Python web applications are built upon the work done by thousands of open source programmers. Application dependencies include not only web frameworks but also libraries for scraping, parsing, processing, analyzing, visualizing, and many other tasks. Python's ecosystem facilitates discovery, retrieval and installation so applications are easier for developers to create.
Python libraries are stored in a central location known as the Python Package Index (PyPi). PyPi contains search functionality with results weighted by usage and relevance based on keyword terms.
Besides PyPi there are numerous resources that list common or "must-have" libraries. Ultimately the decision for which application dependencies are necessary for your project is up to you and the functionality you're looking to build. However, it's useful to browse through these lists in case you come across a library to solve a problem by reusing the code instead of writing it all yourself. A few of the best collections of Python libraries are
Python.org's useful modules which groups modules into categories.
GitHub Explore Trending repositories shows the open source Python projects trending today, this week, and this month.
This list of 20 Python libraries you can’t live without is a wide-ranging collection from data analysis to testing tools.
Wikipedia actually has an extensive page dedicated to Python libraries grouped by categories.
Dependencies are installed separately from system-level packages to prevent library version conflicts. The most common isolation method is virtualenv. Each virtualenv is its own copy of the Python interpreter and depedencies in the site-packages directory. To use a virtualenv it must first be created with the virtualenv command and then activated.
The virtualenv stores dependencies in an isolated environment. The web application then relies only on that virtualenv instance which has a separate copy of the Python interpreter and site-packages directory. A high level of how a server configured with virtualenv can look is shown in the picture below.
The recommended way to install Python library dependencies is with the pip command when a virtualenv is activated.
Pip and virtualenv work together and have complementary responsibilities. Pip downloads and installs application dependencies from the central PyPi repository.
The pip convention for specifying application dependencies is with a requirements.txt file. When you build a Python web application you should include a requirements.txt file.
Python projects' dependencies for a web application should be specified in the requirements.txt with pegged dependencies like the following:
django==1.6 bpython==0.12 django-braces==0.2.1 django-model-utils==1.1.0 logutils==0.3.3 South==0.7.6 requests==1.2.0 stripe==1.9.1 dj-database-url==0.2.1 django-oauth2-provider==0.2.4 djangorestframework==2.3.1
Pegged dependencies with precise version numbers or Git tags are important because otherwise the latest version of a dependency will be used. While it may sound good to stay up to date, there's no telling if your application actually works with the latest versions of all dependencies. Developers should deliberately upgrade and test to make sure there were no backwards-incompatible modifications in newer dependency library versions.
There is another type of dependency specification for Python libraries known as setup.py. Setup.py is a standard for distributing and installing Python libraries. If you're building a Python library, such as requests or underwear you must include setup.py so a dependency manager can correctly install both the library as well as additional dependencies for the library. There's still quite a bit of confusion in the Python community over the difference between requirements.txt and setup.py, so read this well written post for further clarification.
Jon Chu wrote a great introduction on virtualenv and pip basics.
"A non-magical introduction to virtualenv and pip breaks down what problems these tools solve and how to use them.
Tools of the modern Python hacker contains detailed explanations of virtualenv, Fabric, and pip.
Occasionally arguments about using Python's dependency manager versus one of Linux's depenency managers comes up. This provides one perspective on that debate.
This Stack Overflow question details how to set up a virtual environment for Python development.
An alternative approach for managing dependencies with Docker instead of through virtualenv is explained in this post entitled "Using Docker as a Python Development Environment."
Ensure the libraries your web application depends on are all captured in a requirement.txt file with pegged versions.
An easy way to capture currently installed dependencies is with the
pip freeze
command.
Create a fresh virtualenv and install the dependencies from your
requirements.txt file by using the pip install -r requirements.txt
command.
Check that your application runs properly with the fresh virtualenv and only the installed dependencies from the requirements.txt file.


Tools and Utilities
Manual Guide
Auto-Select Star
Calibration Details
PHD2 Server
Dithering Operations
Logging and Debug Output
Polar Alignment Tools
Lock Positions
Comet Tracking
Guiding Assistant
Equipment Profiles
Ask for Coordinates Aux Mount
Simulator Parameters
Multiple Program Instances
Keyboard Shortcuts
Software Update
Manual Guide
If you are connecting to a new mount and are encountering calibration
problems, you will probably want to be sure that PHD2's
commands are
actually getting to the mount. Or you may want to nudge the mount or
experiment with manual dithering. In the 'Tools' menu, click on
'Manual
Guide' and
a dialog will appear to let you move the mount at guide speed in any
direction. If you have an
adaptive optics device attached, you'll see separate move buttons for
both the AO and the secondary mount. Each time you press the button, a pulse of the duration
specified in the 'Guide Pulse Duration' field will
be sent. The default value is the 'calibration step-sze' set in
the Advanced Options dialog. If you are debugging mount/calibration
problems in the daytime, listen to (rather than watch) your mount to determine if it is getting
the commands from PHD2. The idea here is just to figure out if the
mount is responding
to PHD2's
signals. You won't be able to see the mount move (it's moving
at guide speed)
but you may be able to hear the motors. Other options include watching
the
motors and gears or
attaching a laser pointer to your scope and aiming it at something
fairly far away (to amplify your motions). A better approach
for nighttime testing is to run the "star-cross" test described here.
Dithering
is used primarily with image capture or automation applications through the PHD2 server interface. However, you can do
manual dithering or experiment with dither settings using the controls
at the bottom of the dialog. The 'dither' amount field at the
left controls the amount the mount will be moved , in units of
pixels. You can scale this amount - i.e. multiply it by a
constant - by using the 'scale' spin control to the right. These
two controls establish a maximum amount of movement that will be used
for dithering - the product of 'scale' X 'dither'. When you click
on the 'Dither' button, PHD2 will move the mount by a random amount
that is less than or equal to the limit you have set, in one of the
north/south/east/west directions. The 'RA Only' checkbox will
constrain the dither adjustments to only east or west. Obviously,
if you are doing a manual dither in this way, you'll want to be sure
your imaging camera is not in the middle of an exposure.
Auto-Select Star
Clicking on 'Auto-select Star' under the 'Tools' menu, or using the keyboard
shortcut of <Alt>S, tells PHD2
to scan the current guide image
and identify a star suitable for guiding. PHD2 will try to select
a star of sufficient brightness that is not
saturated, not near another star, and not too close to the edge of the
frame. The
selected star may appear fairly dim on the screen, but that's usually
not important - just adjust the gamma slider on the main window.
The auto-select function will usually do a better job than
you can just looking at the display. In many cases, a star
you choose interactively is at or near saturation and will produce
sub-par results. You can use the Star Profile tool
to examine the properties of the selected star, however it was chosen. If you want to use Auto-Select, you should
definitely use either a bad-pixel map or dark library to reduce the
likelihood of PHD2 mistakenly choosing a hot pixel.
Calibration Details
Most of the calibration-related windows, including calibration sanity-checks, will open a window that looks something like this:
The
first thing to look at is the graph to the left, which shows what star
movements resulted from the guide pulses that PHD2 sent during
calibration. The lines represent the RA and Dec guide rates that
were computed as a result of the calibration, and these lines should be
roughly perpendicular. The data points will never be perfectly
aligned, but they should not have major curves, sharp inflections,
or reversals in direction. Particularly with longer focal length scopes, the
points will often show considerable scatter around the lines, but this
is normal. The solid points (west and north pulses) are used to
compute the RA and declination rates, while the hollow points show the
"return" paths of the east and south moves. These can help you
see how much fluctuation occurred due to seeing and also whether there
is a significant amount of backlash. If you are using the
"fast-recenter" option in the Advanced Settings, there may be many
fewer points shown in the east and north paths. The tabular
information to the right
shows what was known about the pointing position of the scope and the
various ASCOM settings that relate to guiding. If you are not
using an ASCOM mount and don't have an "Aux mount" specified, some of
this information will be missing. The table will also show
the expected guiding rates for a "perfect" calibration using
the same sky position and guide speed settings you used. You will
almost never achieve these ideal values, and you shouldn't worry about
them unless your values are very different. If you didn't see an
alert message when the calibration completed, your results are probably
good enough. If you want to re-use a calibration for an extended
time, it is probably worth a few extra minutes to check this
information and confirm that the calibration went
reasonably well and produced sensible results. Bad calibrations
can occur even for very experienced imagers using high-end mounts, so
it is good to check.
If you are having consistent problems getting alert-free calibrations, you should review the material in the trouble-shooting section .
Other Calibration-Related Menu Options
Calibration data are saved automatically each time a calibration sequence completes
successfully. The use of the calibration data has been described
elsewhere (Using PHD Guiding),
including options for restoring calibration data from an earlier
time or "flipping" it after a meridian flip. You access these
functions using the 'Modify Calibration' sub-menu under the 'Tools' menu. Two other
calibration-related items are shown there, namely the options to
clear the current data or to enter calibration data manually. The
"clear" option accomplishes the same thing as the 'Clear calibration'
checkbox in the Advanced Dialog - it will force a recalibration
whenever guiding is resumed. The 'Enter calibration data'
option should be used only under
very unusual circumstances and only if you're sure you know what you're
doing; but it is available as a matter of completeness. If you
click on the 'Enter calibration data' item, you'll see a dialog box
that allows input of relatively low-level calibration data. This
data might come from a much earlier session, perhaps extracted from the
PHD2 guiding log file.
Keep in mind, if you are using an ASCOM driver for either the
'mount' or 'aux mount' connections, you should have little need for
these calibration data controls.
PHD2 Server
PHD2 supports third-party imaging and automation applications that need to control the guiding process. Stark Labs' Nebulosity program
was the first to do this, but other applications have subsequently been
produced. By using the PHD2 server process, image capture
programs can control dithering between exposures or suspend guide
exposures while the primary imaging camera is downloading data.
To use these capabilities with a compatible application, you
should click on the 'Enable Server' option under the 'Tools'
menu. The server interface has been reworked substantially in
PHD2, and it's now possible
for an application to control most aspects of PHD2's guiding operations. Documentation for the
server API is available on
the PHD2
Wiki.
Dithering
The primary purpose of dithering is
to make post-processing easier by removing some kinds of fixed-pattern
noise in the images, especially hot pixels. This is almost purely
a function of the camera you're using and to a lesser extent, the
sophistication of the post-processing software. For imagers
with temperature-regulated, low-noise cameras, dithering is mostly
a convenient way to eliminate hot pixels that aren't getting
removed by the dark frames. Hot pixel positions change as sensors
age, so dark libraries don't usually correct for all of them. Those hot
pixels can also be also removed in post-processing, but that becomes
tedious if there are lots of them. It's also possible that
dithering can help with some other kinds of sensor behavior such as
column defects, and it's particularly helpful if there is no
temperature regulation on the sensor and therefore no good way to use a
dark library. DSLR imagers often use aggressive dithering for
those reasons. In the PHD2 implementation, automated
dithering is accomplished through the server interface, so make sure
you have 'Enable Server' checked under the 'Tools' menu. You
first specify a maximum dither size you want to use during the
guiding session - this will be set in your imaging application.. Then,
when that application issues a dither command, PHD2
uses a random number generator to decide how large the dither will
actually be for that command. The actual dither mount will be
> 0
and <= the maximum amount allowed. You want to use pseudo-random
dither amounts like this to be sure that dithering doesn't follow a
consistent pattern or shift the frame back to a location where it has
previously been. But for some of the applications that do PHD2
dithering, you
can't specify the maximum amount directly - you are perhaps limited to
choices like small/medium/large and the max dither amounts will have
preset values. For that reason, PHD2 has a dither scaling
parameter in the 'Global' tab of the Brain dialog. It is
basically a multiplier term that lets you adjust the range of dither
amounts that are possible. So a scale factor of 1 doesn't change
the
preset value at all, a value of 10 multiplies it by 10X, etc. If
you're using an app that lets you specify the maximum amount directly
(e.g. PHD_Dither), you should leave the dither scale set to 1.0.
Otherwise, you can adjust the scale factor if you aren't
happy with the overall range of dithering you're getting with one of
the small/medium/large type imaging apps.
There are typically
two costs associated with dithering: 1) the extra time and uncertainty
required for "settling" and 2) the need to crop the final stacked frame
in order to remove the low-signal margins. Settling is the term
used for a period of stabilization after the mount has been moved by a
dither command. The imaging app that starts the dither will also
decide when the guiding has stabilized enough to continue
imaging. The app can let PHD2 determine this by specifying the
settling parameters or the app can do the calculations itself.
You'll need to look at your imaging/dithering app to see what control
you have over this process. If the app uses the latest PHD2
server interfaces, it can specify a settling requirement that might
look like "guiding errors must be less than 1.5 pixels for a period of
at least 10 seconds." This is a process that can consume some
time, depending on how tight the requirements are for settling.
It is likely to take more time if you are dithering in declination and
the dither forces a change in direction. Most mounts have some
declination backlash, so it can take a number of guide commands to get
the mount moving in the right direction, and then more time for the
process to converge on the new target location for the guide
star. That's why PHD2 also offers the option to dither only in
right ascension. Again, this is an option on the 'Global' tab,
right next to the dither scaling parameter.
If
your mount has a substantial amount of declination backlash in the
mount, you may be guiding in only the north or south Dec direction.
If PHD2 receives a command to dither in declination while you're
operating in this mode, it will temporarily allow guiding in both Dec
directions until the dither and settling are completed. It will
then revert to the original north/south-only guiding mode. If you
don't want this behavior, you should restrict dithering to 'RA-only'
('Global tab of the Brain dialog).
Logging and Debug Output
PHD2 automatically creates two types of log files: a debug log and a
guiding log. Both are very useful for different reasons.
The guiding log is similar to the one produced by PHD, but
with
extended information. The guide log is intentionally formatted to
allow easy interpretation by either a human reader or an external
application. For example, the very capable PHDLogView application (not
part of the PHD2 release) can produce a variety of graphs and summary
statistics based on data in the PHD2 guide log. But the log can also be easily imported into
Excel or other applications for analysis and graphing.
When importing into Excel, just specify that a comma should be used as a
column separator. The
debug log
has a complete record of everything that was done in the PHD2
session, so it is very helpful in isolating any problems
you have. It also employs a human-friendly (albeit verbose)
text format, so it's
not
difficult to examine the debug log to see what happened. If
you
need to report a problem with the software, you will almost certainly
be asked to provide the debug log file. If you have neither log
file available, you are unlikely to get any help.
The location for the files is controlled by the 'Log
File
Location' field in the 'Global' tab of the 'Advanced Settings' dialog. By default, log
files
are stored in the OS-specific default directory for user documents.
In Windows7, for example, the files will be stored in a 'PHD2'
sub-folder in the "Documents" directory. This may not be a
convenient location, so you can specify a different folder using this
edit field. In order to prevent excessive accumulation of log
files, PHD2 automatically removes debug logs that are more than 30 days
old and guide logs that are more than 60 days old. If you want to
retain the files for longer periods, you should move or copy them to a
different folder location, one not used by PHD2.
In some unusual cases, you may need to capture guide
camera images, usually to support debugging and problem resolution.
This can be done by clicking the 'Enable Star Imaging Logging'
menu item under the 'Tools' menu. The resultant image files will
be stored in the same location as the other log files. The format
of these image files is controlled from the 'Global' tab of the
'Advanced Settings' dialog. If you are trying to document a
problem you're having, you should choose the 'Raw Fits' format for
maximum flexibility.
Automatic Log File Upload
If you need help using PHD2 or improving your guiding results, you'll want to post a request on the Open-PHD-Guiding
forum (https://groups.google.com/forum/#!forum/open-phd-guiding).
Your question should be accompanied by the PHD log files
associated with the guiding session you're talking about. To make
that easier, PHD2 has a built-in function to select, compress, and
automatically upload the relevant log files. That function is
located on the 'Help' menu. You'll see a dialog box that shows
all the available log files, including their timestamps and duration:
Just
select the files you want and start the upload process by clicking on
'Next'. If PHD2 is generally working for you but you can't
interpret the guiding performance or you want to improve it, you can
start by just uploading the guide logs. But if you're having
trouble with camera or mount connections or otherwise can't get PHD2
running, you should also include the matching debug log file. Be
selective about the files you choose - just the files for the session
you were having trouble with. When the upload process is
complete, you'll see another window that gives you a link to the files:
You
need to capture or record that link so it can be included with the
question you'll post on the forum. Log files will be
automatically removed on the server after a reasonable amount of time
has elapsed, so you won't need to worry about that. When you post
your request for support, please include a full description of what you
were doing, whatever problem you saw, and roughly what time period you
want us to focus on.
Polar Alignment Tools
PHD2 offers three different polar alignment tools. The three approaches share the same basic
objective: to help you physically align the RA axis of your mount to the
celestial pole. These polar alignment
tools are different from the “two-star” or “three-star” alignment procedures
that are part of most popular go-to mounts.
The mount software routines are generally focused on optimizing go-to
operations, correcting the slewing/pointing operations for a variety of errors
in the mount, including polar alignment error.
They generally don’t involve physical adjustment of the mount’s azimuth
and altitude controls, which is what is necessary for successful imaging and
guiding.
The original polar alignment routine, drift alignment, is
still considered by most to be the “gold standard” for accuracy. Partly, this is because it directly measures
the thing you’re interested in: the amount of drift that will be caused by
mis-alignment of the RA axis on the celestial pole. The drift alignment tool requires use of only
one visible star at a time, and identification of the star is unnecessary. But the procedure can be time-consuming,
especially for beginners, because each mount axis must be adjusted separately
and the telescope will need to slew over a fairly wide area. Also, it works best if you have clear views
of the celestial equator/meridian intersection and an area around 30 degrees
above either the eastern or western horizon (azimuth 90 or 270 degrees). For imagers who are rushing to set up each
night or have a limited view of the sky, these requirements may be
unattractive.
The second alignment option, static polar alignment,
addresses these concerns by taking a different approach. It specifically trades off a bit of accuracy
to optimize the speed of the process. It
requires only a clear view of the northern or southern polar region, and it
facilitates adjustment of both mount axes at the same time. It is therefore a bit more intuitive and quite
likely to be quicker to complete. It
does require visibility and identification of several stars near the pole, but
the tool makes that reasonably easy assuming your sky conditions are good
enough to see the stars.
The third alignment option, polar drift alignment, is probably the
simplest one to perform at the expense of a bit of accuracy and speed.
It
requires a clear view of the northern or southern polar region, and it
facilitates adjustment of both mount axes at the same time. Minimal
user input is needed so it is very simple to use.
The three techniques are described in detail in the following
sections. Imagers should probably
experiment with them and choose the one that best suits their
needs. The importance of alignment
accuracy is often over-emphasized, so users need to keep things in
perspective. Most declination drift can
be well-managed by PHD2 guiding assuming the mount behaves well and doesn’t
have a lot of declination backlash.
However, at some point, the amount of polar alignment error can create
field rotation in the images, something that can’t be corrected. The larger the imaging sensor and the closer
to the pole the target is, the more field rotation can be an issue. You can compute the expected field rotation
using an online calculator such as this one:
http://celestialwonders.com/tools/rotationMaxErrorCalc.html
The calculator can help you decide how much accuracy is
“good enough” for your situation. It’s
also important to remember that either procedure can be limited by the
precision of the adjustment mechanisms on the mount.
Lock Positions
PHD2 normally
sets a 'lock position' where the guide star is located at the end of
calibration. Depending on the details of the calibration
sequence, this may not be exactly where the star was located at the
start of calibration - it could be off by a few pixels. If you
are trying to precisely center your target, you may want to use a
'sticky lock position.' You do this by clicking on your guide
star before calibration, then
setting the 'Sticky Lock Position' under the 'Tools' menu. After
calibration is complete, PHD2 will continue to move the mount until the
star is located at the sticky lock position. So you may see
an additional delay after the calibration while PHD2 repositions the
scope at guide speed. The sticky lock position will continue to
be used even as guiding is stopped and subsequently resumed.
Again, this insures a rigorous positioning of the guide star (and
presumably your image target) at the expense of delays needed for PHD2
to reposition the mount.
If
you need to fine-tune the position of the guide star on the
camera sensor after guiding has begun, you can use the 'Adjust Lock
Position' function under the Tools menu:
You
can nudge the guide star in small increments (at guide speed) or you
can move it by a larger amount by typing in a new lock position
and clicking 'Set'.
Clicking on the up/down/left/right buttons will cause the lock
position to be shifted in the corresponding direction by the amount
shown in 'Step', and the revised lock position will be displayed
If you type in a new lock position, you run the risk of losing
the guide star if the new position falls outside the current
search region. This tool is useful if you need to achieve
precise positioning of either the guide star or the imaging target, for
example with spectroscopy..
Comet Tracking
One way to image a comet is to have PHD2 use the comet as the guide
"star", but this approach may not always work. For example, the head
of the comet may not present a star-like center suitable for
guiding. Or, when using an off-axis guider, the comet may not even be
visible in the guide camera.
PHD2 provides a Comet Tracking tool for use when guiding on the comet
itself is not feasible. The idea is to guide on an ordinary star, but
to gradually shift the lock position to match the comet's motion,
or tracking rate.
There are a three different ways to provide the comet tracking rate to PHD2.
- Some planetarium applications, like Cartes du Ciel, can send the rate directly to PHD2;
- You can enter the tracking rate manually, or,
- You can train the rate in PHD2 by following the comet for a period of time in the imaging camera.
To enter the rate manually, you would select "Arcsec/hr" for units and
"RA/Dec" for axes, then enter the rates from the comet's ephemeris.
Comet rate training works like this:
First, center the comet in your imaging camera. If your imaging
application has some kind of reticle display, you should use that to
note the precise position of the comet on the imaging sensor. Once
this is ready, select a guide star in PHD2 and start guiding. Next
click "Start" in the Comet Tracking tool to begin training.
Take a continuous series of short exposures in your imaging camera
using your imaging application's Frame and Focus feature. Over time,
the comet will drift away from the starting location. Use PHD2's
"Adjust Lock Position" controls to move the comet back to the starting
location. You may have to experiment a bit to determine which way the
comet moves on the imaging camera sensor in response to the
Up/Down/Left/Right controls in PHD2. You may find it useful to enable
the "Always on top" button in the Adjust Lock Position window so the
controls stay visible on top of your imaging application.
PHD2 will quickly learn the comet tracking rate as you re-center the
comet. Once you are satisfied that PHD2 is tracking the comet, you can
click Stop to end the training. PHD2 will continue shifting the lock
position to track the comet until you disable comet tracking by
toggling the Enable/Disable button.
You can practice the comet training technique using the built-in
camera simulator. Check the "Comet" option in the Cam Dialog, and the
simulator will display a comet. Use a bookmark to mark the comet's
starting location, and use the Adjust Lock Position controls to move
the comet back to the bookmark location.
Guiding Assistant
The
Guiding Assistant is an instructional tool to help you measure
current seeing conditions and the general behavior of your mount and
guiding
subsystem. When it's run, it temporarily disables guiding output
and measures the ensuing motion of the guide star. This can help
you
see the high-frequency motions caused by seeing (atmospheric)
conditions. These cannot be corrected by conventional
guiding because they occur at a much higher frequency than you can
typically even measure. Trying to correct for them with conventional
guiding is often called "chasing the seeing" and usually leads to
poor results. Avoiding it is best accomplished by
setting a minimum-move level that will cause PHD2 to ignore most of
this high-frequency behavior. The Guiding Assistant can also show
you other behavior of your system such as overall drift
rates in right ascension and declination as well as peak-to-peak and
maximum-rate-of-change measurements in
right ascension,. While these things can usually be "guided out",
measuring them can be helpful if you want to improve the underlying
performance of the mount - for example, by improving your polar
alignment if the declination drift rate is high. The Guiding
Assistant can also measure the declination backlash in your system if
you select that option in the user interface.
When
you start the Guiding Assistant (GA), its behavior depends on whether
you are already guiding. If guiding is active, the initial screen
will look like this (with different data values of course):
The
topmost field in the form always shows what the GA is doing and what
action you should take, so you should always look there first if you
don't know what's happening. In this case, the measurement
process has been started automatically and you should simply let it run
for at least two minutes. The text field immediately above the
buttons also summarizes what's happening. The three buttons are
enabled or disabled based on the operating state of the GA. In
this case, 'Start' is disabled because the measurement is already
underway.
If you launch the GA when guiding is inactive, the initial form will look different:
In
this case, you'll need to first start guiding in PHD2 - start looping,
select a star, and guide. Once that's done, the 'Start' button in
the GA will be enabled and you can begin measurement.
When GA measurement is active, guiding commands will be disabled, so the star
will appear to wander around on the display - this is entirely normal.
As guider images are acquired, statistics are computed and
displayed in real-time in the user interface. Of particular interest
are the table entries for "High-frequency Star Motion" and "Polar
Alignment Error". After about two
minutes of data collection, these numbers will usually stabilize and
you'll have reasonable measurements. If you want to get a
more accurate measure of your polar alignment error
and any uncorrected periodic error in RA, you'll need to let the
Guiding Assistant run for up to 10 minutes. Also, the computed polar
alignment error is sensitive to the current scope declination. To
get the most accurate measurement, you should point the scope to within
a few degrees of the celestial meridian. When you finally click
the 'Stop'
button, this phase of the measurement process will stop.
If
you've checked the box to 'Measure Declination Backlash" that process
will commence (see below). If not, guiding commands will be
re-enabled and the data collection
process will end. Other computed results will be displayed
in the lower area of the table showing overall drift rates and various
other measurements. All of these values are displayed in
units of both arc-seconds and pixels. The dialog box will look
something like this:
The
contents of the 'Recommendations' group on the right side of the window
reflect the results of the statistical measurements. Assuming
your chosen guide algorithms support a minimum-move property, you have
the option of automatically setting those parameters based on the
results. You can also decide to re-run the measurements or close
the dialog box altogether if you want to proceed with normal guiding
operations.
Measuring Declination Backlash
If
you've checked the box to 'Measure Declination Backlash',
that process will begin as soon as the high-frequency measurements
are completed. In other words, clicking once on the 'Stop' button
halts the high-frequency measurements and begins the measurement of
declination backlash. However, if the initial sampling period was
less than 2 minutes, a dialog box will appear and the backlash test
will continue to sample until the 2-minute period has expired. A
new group of status messages will be
shown immediately above the 'Start' and 'Stop' buttons so you can see
what's being done:
To
do backlash measurement, PHD2 will move the star by large amounts,
first in the north direction, then back to the south. There is
some risk the star will be lost during this process or the star might
already be too close to the north edge of the sensor. You
should choose a guide star that has plenty of room to move north
to get the best accuracy. If the star is lost because it's been
moved outside the search region, you can temporarily increase the size of that region from
the 'Guiding'
tab of the Advanced Settings dialog.
A search region size of 20 pixels should work for most
configurations - just be sure you don't have multiple stars inside the
search region. The first phase of backlash measurement involves
an initial attempt to clear whatever backlash is present in the north
direction. The Guiding Assistant (GA) will continue with these
clearing commands until it sees a significant and consistent movement
of the
guide star in one direction. Once this is done, the GA will issue
another sequence of commands to continue moving the star north by a
large amount.
This will take at least 16 seconds and may take longer depending
on the configuration - you can watch the status update to see what's
being done. When the north steps are finished, the GA will issue
an identical number of steps in the south direction. If there's
significant backlash in the mount, it may take a long time for the star
to start moving south, but that will usually be handled. Once the
south steps are done, regardless of how far the star has actually
moved, the backlash amount will be computed. However, if the star hasn’t moved at all in the south
direction, the computed backlash amount will be too small. At that point, you can know your declination
backlash exceeds 8 seconds, which is a very large amount.
The Guiding Assistant will then try to move the star back to its
starting position and will re-enable guiding. Again, there is
some risk the star may be lost, but this won't affect the calculations
- you can simply stop and resume guiding as you normally would.
Unlike the first process for measuring high-frequency star
movement, you don't need to click on the 'Stop' button once backlash
measurement has begun. The measurement process will terminate
when all the steps have been completed, and normal guiding will be
resumed. However, you can click on the 'Stop' button if something
has gone wrong - such as a lost-star condition - and then restart when
you're ready. When the backlash tests are finished, you'll see
the results
displayed as before, with the addition of entries for the amount of
declination backlash and the measurement uncertainty::
Depending
on the amount of backlash, you may see a recommendation for setting a
backlash compensation factor - 230 ms in the example shown above.
This type of backlash compensation is different from the feature offered in many mount controllers and is described here: PHD2 backlash compensation If the measured amount is less than 100 ms, no recommendation
will be made because such a small amount probably doesn't warrant any
compensation. If the backlash is very large, over 3 seconds,
you'll see a different recommendation to use uni-directional guiding in
declination. That's because trying to compensate for such large
values probably won't work very well, and the mount will probably not
be able to reverse directions quickly enough to support bi-directional
guiding. Obviously, you can reach your own conclusions based on your
experience with how the mount behaves. Before doing these
measurements, be sure to disable any backlash compensation that's
previously been
enabled in the mount software. If this isn't done, the
measurements and
any subsequent attempts at compensation by PHD2 will be invalid.
If you want to try uni-directional guiding, you can find
instructions here: Uni-directional guiding
You
can look at a graphical display of the backlash measurement results to
get a better understanding of how the mount performed. Just click
on the 'Show Graph' button to see a graph that might look something like
this:
The
green points show the measured declination positions, shown left to
right, beginning with the north moves and ending with the south
(return) moves. The white points show the south-return behavior
for a perfect mount with zero backlash. In this example, there is
only a small amount of backlash as evidenced by the flattened top of
the green
points. However, the flattened top will be more pronounced when
there is significantly more declination backlash in the mount, as in
the following example:
In
some cases, the backlash measurement will report a failure and
won't display a numerical result. This can happen if
the guide star is lost, but a more likely cause is a combination of
large backlash and stiction (static friction) on the Dec axis or a
large imbalance in Dec. In those case, the south moves may never
show a consistent movement of the expected size so the measurement will
simply be too inaccurate. Even if the test fails, you'll still be able
to look at the graph so you'll be able to see how the mount performed
during the test.
The 'Review Previous' button at the bottom of
the window lets you review the previous three GA results. If
you've run backlash tests at any time, at least one of the three
sessions will include a backlash measurement result. Clicking on
the 'Review' button displays a list of timestamps when a GA was run for
the current profile, so you can just select the date/time you want.
All the grid values and recommendations will be filled with the
results from the selected GA run, including active buttons for applying
the recommendations.
Star-Cross Tool
The star-cross tool can help you test the mount's response to guide commands as described in this trouble-shooting
section. Although the test is easy to perform manually, you may prefer
to use this tool. The star-cross tool will show the following
dialog:
This test presumes you're using the main image camera to expose the image,
so PHD2 doesn't know what image scale is being used for that.
You'll need to be sure the settings are large enough to show a
distinct
pattern on the main camera but not so large that the stars will move
out of the field of view. The default settings should work well
for most set-ups but you can adjust them as needed. The important
thing is to get a clear record of the movement of the stars in the main
camera image and to save that image in a raw, uncompressed format (eg.
FITs or uncompressed TIF). During this test, looping will be
active but no guide star will be selected, and it doesn't matter if
individual stars move out of the guide camera frame. Looping is
activiated just so you get some quick visual feedback on whether the
mount
is moving.
Meridian flip calibration Tool
The meridian flip calibration tool is used to automatically determine
the correct value for the setting Reverse Dec output after meridian flip.
Running the tool involves two calibrations -- one with the telescope
on the East side of the pier, and one on the West. You will be
instructed to slew the telescope when needed.
Managing Equipment Profiles
Equipment profiles were introduced in the section on Basic Use
where they are used as part of the 'Connect Equipment' dialog. If
you want to manage multiple profiles, you will probably want to use the
'Manage Profiles' button in the 'Connect Equipment' dialog. Using
the menu items there, you can create a new profile
or edit/rename/delete an existing one. Each profile holds
all the settings that were active at the time the profile was last
used. If you create a new profile, you can import these settings
from either the PHD2
generic defaults or from an existing profile. You can also use the
'Wizard' option to have PHD2 establish settings that are specific to
your equipment configuration. To
edit the settings in an existing profile, you first select it in the
equipment profile drop-down list, then click on 'Settings' under the
'Manage Profiles' pull-down. This will take you to the 'Brain'
dialog, where you can make whatever changes you want. Remember
than profiles are automatically updated anytime settings are changed
during a PHD2 session. Finally, you can import and export
profiles for purposes of debugging, backup, or even exchange with other
PHD2 users.
Aux-Mount Connection using "Ask for coordinates"
If
you can't connect to your mount using either ASCOM or INDI drivers, you
still have a better-than-nothing alternative by using the "Ask for
coordinates" aux-mount connection. With this option, you'll be asked
to enter or confirm the scope position each time guiding is going
to begin::
If
you enter your scope's current declination and side-of-pier values,
PHD2 will automatically adjust the calibration to match that
pointing position. You don't need to be precise, a
Declination value that's within a few degrees will work. This
means you won't need to recalibrate as you slew to different targets
so long as you update these values each time. For
example, you can do a calibration near Declination=0 then enter
new position values when you've slewed to a high declination imaging
target.
This is likely to produce a better result than trying to
calibrate at a near-pole position. This dialog will not be
displayed if the start of guiding is the result of a dither operation
or a server command from an imaging application. In order for the
calibration adjustment to work correctly, your previous calibration must have been completed with correct positioning data available.
If you're using this option with the Drift Alignment tool, the dialog will look a bit different:
If
you enter the additional information for Right Ascension, latitude, and
longitude, the Drift Alignment tool can more accurately adjust its
magenta target circle. Otherwise, the circle will show only an
upper-bound estimate of the pointing error during the 'adjustment'
phases.
You
can connect or disconnect the "Ask for
coordinates" aux-mount without affecting the camera or mount
connections. So you might decide to use the option for drift
alignment or for an initial slew to your imaging target, then
disconnect from it in order to avoid
the repetitive dialog displays. Regardless of how you choose to
use it, you're
responsible for having the correct values in place, and you should
remember that significantly wrong values can result in poor guiding
results.
Advanced Settings for the Simulators
The device simulators were introduced in the Basic Use
section as useful tools for you to experiment with PHD2 and become
famliar with its features. Remember that you must choose
'Simulator' as the camera type and 'On-camera' as the mount type in
order to get the benefits of simulation. As you become more
interested in the details of the simulation, you can use the 'Cam
Dialog' button on the main display to adjust the simulation parameters:
You can adjust simulated mount behaviors for declination backlash, drift
due to polar mis-alignment, and periodic error. You can also
adjust the 'seeing' level, which will create fairly realistic guide
star deflections that look like seeing effects. If you adjust
these parameters one-by-one, you'll see how they affect star
deflections and how the different guide algorithms react to those
movements. Of course, you're dealing with a "nearly perfect" mount in
these scenarios (except for backlash), so the simulation can't be entirely realistic.
Multiple Program Executions
In
some situations, you may want to run multiple instances of PHD2 at the
same time. To start the second instance of PHD2, you need to
supply a command-line parameter of -i 2; the third instance would be
started with -i 3, etc. You can accomplish this in Windows by
running PHD2 from a command line using the Windows cmd.exe utility.
Or you can create a Windows desktop shortcut by doing the
following:
Right-click on your desktop
Select: New/Shortcut
Enter the following string to identify the location of the program: "C:\Program File (x86)\PHDBuiding2\PHD2.exe" -i2
Click Next
Enter a name for the shortcut, e.g. PHD2 #2
Click Finish
Note the quotes around the name in the 3rd line are required by Windows because there are blanks embedded in the directory name.
Keyboard Shortcuts
Keyboard
shortcuts are available for many of the more commonly used tools and
functions in PHD2. These are enumerated in the Keyboard Shortcuts section.
Software Update
One of the most common responses to a request for support in the PHD2
Forum is: please upgrade to the latest version and see if the problem
still exists. If you are seeing an issue in an older version of PHD2
it is quite likely that you are not the first person to encounter it,
and that it has already been reported and fixed in a newer version of
PHD2. For this reason, the developers of PHD2 feel that it is
important to be running the most up to date version of the program.
Upgrading a program that you rely on for unattended imaging in our
limited available clear sky time can sometimes be perceived as a risky
proposition. The developers of PHD2 recognize this sentiment--we are
imagers too! There is a necessary trade-off between maintinaing a
stable software installation, and of updating to receive the latest
bug fixes and other improvements.
PHD2 achieves a balance between these two opposing needs by
publishing two series of software releases. The development releases
contain the latest ongoing bug fixes and feature improvements, and are
tested by the developers--usually during actual imaging time--before
being released. Users who choose to run the development releases will
get the latest bug fixes and newest features. Development releases
have names like "2.6.3dev6" indicating, for example, the 6th
development release after the 2.6.3 major release.
Periodically, after a development release has received more test
time, it will be published as a major release. For example, 2.6.3dev6
could be published as major release 2.6.4.
Checking for updates
PHD2 has an option to automatically check for software updates. We
recommend enabling this option to help keep your version of
PHD2 up to date. When the automatic check option is enabled, PHD2 will
quietly check for updates in the background when PHD2 starts. If new
updates are available, PHD2 will give you the option to install the
new version. Enabling the automatic check for updates will not
interfere with the ordinary operation of PHD2, including automated
operation. It is also safe to leave the option enabled if you are
imaging in the field without internet connectivity. If PHD2 cannot
check for updates, it will wait until next time it is started before
trying to check again.
Regardless of whether you allow PHD2 to automatically check for
updates at startup, you can always manually check for updates by
clicking "Check for updates" from the Help menu.


Marcus Lazaro, hoping to get hired by you!
- 742 Bremerton PL NE Renton, WA 98059
- Call me:<PHONE_NUMBER>
- Email<EMAIL_ADDRESS>I’m Marcus, American Filipino at age 20, currerntly a student at Bellevue College. I'm looking for a job to help myself in this hard world we live in. Seeing you carry that world from underneath makes me want to help you save your back from breaking
Starbucks Barista


I assume that you already aware of how to host free website using github pages on their subdomain yourdomain.github.io. But this article is about how you can add multiple github pages website into your same account. Yes you don't need to create separate github account to host your free github pages website to a custom domain. What you need a new repository in your github account and a domain. Lets get started
1. First you need to create a new repository in your github account. Go to your repositories page and click on new button.
2. Then give any name to your repository and add some description in it. By default make this repository to Public so that it can access on the web
3. Once your repository get created then route to repository main page and create a new branch in it named "gh-pages"
4. Push all your website files into this branch (gh-pages) along with a .txt file names CNAME.
5. In this CNAME file insert your registered domain on which you want this content to be
publish. for e.g
6. Now go to your domain provider's website and redirect to DNS settings page. In my case i am using godaddy services to register my domain. and you need to add the following settings into the DNS.
For A record, set <IP_ADDRESS>, <IP_ADDRESS>, <IP_ADDRESS> and <IP_ADDRESS>. To redirect www subdomain to the original domain, add a CNAME record with your GitHub pages profile URL with a .(dot) in the end, for example, 'YOUR-GITHUB-USERNAME.github.io.'.
Official References: For most up to date IP Addresses, use GitHub's official documentation and for setting up CNAME use this documentation.
Note: These DNS settings could take upto 24 hours to reflect. Your domain will not show the changes until these settings will not update in your domain provider.


Copyright 2020, UPPRO.
Linking farmers with the technology to create competitive advantage has always been a prime objective for UPPRO. On the technology front, following interventions have been done :
Most Farmer Producer Organizations (FPO) are relatively new companies and tend to
operate using manual processes and methods. Day-to-day operations of FPOs require
co-ordination between the shareholder farmers, supporting institutions and other players in the ecosystem like buyers, suppliers and logistics operators. The speed of operations and successful scale-up of an FPO is heavily impacted by the number of people it can hire to manage the daily co-ordination, office and field operations.
Typical FPOs are limited to operate with usually two or three dedicated employees to minimize the cost of operations. Further manual recordkeeping and maintaining multiple record books increases the chances of error and makes reconciliation across business transactions difficult. This makes the case for simple digital tools for FPOs which can help improve the operational efficiency of the FPO workforce and also aid in digitally tracking all business transactions in an easy and secure manner while digitizing the entire business, operations, and financial activities of an FPO.
UPPRO has undertaken FPO digitization with the following objectives:
Total 2 FPOs have been fully digitized with the help of CDFI (Centre for Digital Financial Inclusion, Delhi ). Work is going on in 3 more FPOs to digitize their business operations. The following activities have been completed in FPO digitization:
UPPRO facilitated FPOs in establishing a custom hiring bank /farm machinery bank. 36 FPOs have so far been facilitated in establishing a farm machinery bank The objectives of this intervention has been:


--- layout: post authors: ["Greg Wilson"] title: "Routinely Unique" date: 2015-06-14 time: "19:30:00" tags: ["Noticed"] ---
Back in April, Jeffrey Chang wrote wrote an article for Nature in which he pleaded for those who analyze bioinformatics data to be recognized as creative collaborators in need of career paths. In it, he observed:
To give greater support to researchers, our centre set out to develop a series of standardized services. We documented the projects that we took on over 18 months. Forty-six of them required 151 data-analysis tasks. No project was identical, and we were surprised at how common one-off requests were. There were a few routine procedures that many people wanted, such as finding genes expressed in a disease. But 79% of techniques applied to fewer than 20% of the projects. In other words, most researchers came to the bioinformatics core seeking customized analysis, not a standardized package.
This is why we teach what we teach: almost by definition, if someone is doing research, she's doing things that haven't been done before, and therefore don't (yet) exist in an off-the-shelf package. Just as in the lab, what we can know is limited by what we can do. This is also why teaching testing is hard: each one of the unique analyses Chang identified might need to be checked in a different way.


Hello World!
My name is Cory Gross. I am a software developer graduating in December 2013 from Auburn University. I am interested in building great software that people use, web and mobile development, games, and technology in general. I have a passion for open source and love learning to use new tools. This site is hosted for free on GitHub Pages and was built using Jekyll Bootstrap source platform.
title : My Blog =)
author :
name : Name Lastname
email<EMAIL_ADDRESS>github : username
twitter : username
The theme should reference these variables whenever needed.
Sample Posts
This blog contains sample posts which help stage pages and blog data. When you don’t need the samples anymore just delete the _posts/core-samples
folder.
$ rm -rf _posts/core-samples
Testing Pygments
function () {
return Math.cos(0.5) + Math.sin(0.3)
}
Here’s a sample “posts list”.
- 09 Apr 2013 » Hello World!
- 29 Dec 2011 » Jekyll Introduction
To-Do
This theme is still unfinished. If you’d like to be added as a contributor, please fork! We need to clean up the themes, make theme usage guides with theme-specific markup examples.


EXPOSURE THERAPY WMBR 88.1 FM ALTERNATING SATURDAYS @ 11PM EASTERN TIME
EPISODE 00 - 03.11.17 - WMBR WOMENS WEEK SPECIAL PROGRAMMING
EPISODE 01 - 03.25.17


we prefer SVG implementations for their improved accessibility and vector support.
Here some icons which are built using Icomons
all icons can be accessed by using class prefix icon-
for
example


| Overview | Namespace | Class | Index | Help |
| PUBLIC MEMBERS: | CLASSES | STRUCTS | UNIONS | ENUMS | TYPEDEFS | METHODS | STATIC METHODS | DATA | STATIC DATA |
| PRIVATE MEMBERS: | CLASSES | STRUCTS | UNIONS | ENUMS | TYPEDEFS | METHODS | STATIC METHODS | DATA | STATIC DATA |
template< typename reference_type >
| virtual | abstract | interface | template |
| NO | NO | NO | YES |
Methods |
|
| Reference( ); |
Constructor... |
| Reference( reference_type * pBody ); |
Constructor... |
| Reference( const Reference< reference_type > & handle ); |
Copy constructor... |
| ~Reference( ); |
Destructor... |
| Reference< reference_type > & set( reference_type * pBody ); |
Set... Similar to assignment. |
| Reference< reference_type > & operator=( const Reference< reference_type > & handle ); |
|
| Reference< reference_type > & operator=( reference_type * pBody ); |
Assignment... |
| Reference< reference_type > & clear( ); |
|
| reference_type * get( ) const; |
|
| reference_type * operator->( ) const; |
Probably most common used: handle->someBodyOp(). |
| reference_type & operator*( ) const; |
Allows (*handle).someBodyOp(). |
| sal_Bool is( ) const; |
Returns True if the handle does point to a valid body. |
| sal_Bool operator==( const reference_type * pBody ) const; |
Returns True if this points to pBody. |
| sal_Bool operator==( const Reference< reference_type > & handle ) const; |
Returns True if handle points to the same body. |
| sal_Bool operator!=( const Reference< reference_type > & handle ) const; |
Needed to place References into STL collection. |
| sal_Bool operator<( const Reference< reference_type > & handle ) const; |
Needed to place References into STL collection. |
| sal_Bool operator>( const Reference< reference_type > & handle ) const; |
Needed to place References into STL collection. |
Data |
|
| reference_type * m_pBody; | The <b>reference_type</b> body pointer. |
Copyright © 2012, The Apache Software Foundation, Licensed under the Apache License, Version 2.0. Apache, the Apache feather logo, Apache OpenOffice and OpenOffice.org are trademarks of The Apache Software Foundation. Other names may be trademarks of their respective owners.


--- layout: archive title: Zulip Chat Archive permalink: /stream/113488-general/topic/coinductive.20types.html ---
Can someone (@Simon Hudon ?) explain what a coinductive type is and, more specifically, whether a mathematician would ever need them?
As to the comments about them made here and linked to here, this might be another of those "perfect is the enemy of good" situations where we could either have Simon's "does the job to a certain extent", or the observation that one could do this much better if only we could find a Lean C++ hacker that just sat down and wrote a bunch of complicated working code, I would vote for Simon any day of the week.
We don't need a C++ hacker for this one. I hope to implement the next version of (co)inductive types in lean
@Kevin Buzzard: Non-wellfounded Set Theory might help.
Mathematically, the theory of coinductive types is very elegantly dual to the theory of inductive types. A simple example of a coinductive type is the type of "possibly infinite lists", which is defined with the same clauses as list
This is a type that contains the empty list, finite lists, as well as all infinite lists (a.k.a "streams")
(These are often called llist
or "lazy lists" for reasons to come.) The type llist
has a cases_on
, i.e. you can ask for any llist
whether it is nil or a cons of an element and a llist
, but there is no rec
, because a llist
is not well founded
There's also:
@Tim Carstens
terminal co-algebra of an endofunctor, instead of initial algebra of an endofunctor
if you want to look at them in terms of category theory
llist
are easy enough without coinductive
types but I imagine if you care about (possibly) infinite objects such as trees, it will be hard to study them without coinductive types.
I personally care about them mostly for modelling programs that do not terminate such as operating systems, controllers for pacemakers or any internet protocol
maybe bass-serre theory, aka doing group theory by way of group actions on (infinite) trees
i'm struggling to think up examples from pure math where coinductives would be handy
it's a big world out there though
{% endraw %}Last updated: Apr 24 2020 at 19:02 UTC


23 Jul 2019
This is part 3 of a series about basics of Play framework. In part 2, we covered fundamentals of routing.
In this article, we will cover forms in Play framework. I have personally never seen a functioning web application that does not heavily use forms.
23 Jun 2019
This is part 2 of a series about basics of Play framework. In part 1, we scaffolded a play application using the playframework/play-scala-seed.g8
template and discussed the components in the resulting directory structure.
In this article, we will explore the basics of routing in Play.
23 May 2019
In the previous article, we created a very stripped down REST application with only one controller end point using Play framework and scala. We assembled it piece by piece while going a little deep into what purpose each component in the final directory structure does.
23 Apr 2019
With the advent of modern web frameworks such as Play, Laravel/PHP, Express/Node, advanced tools have come up to help in scaffolding ready-to-run Web Apps with a single command. In some cases, like with Play, there are even fully scaffolded examples to download and run.
20 Feb 2019
In this article, we will explore java.util.Calendar
class.


In Pictures: Spectacular Christmas light show at Kew Gardens
The after-dark trail includes a host of installations.
It’s the most wonderful time of the year at Kew Gardens as the after-dark trail returns to light up the Surrey attraction.
Now in its seventh year, the winter trail takes a magical new route and includes a host of installations including glittering spiral trees, dynamic laser projections, a cascade of glowing silvery shards and changing ribbons of light.


Huawei nova 6 5G with super wide-angle front camera to be unveiled on 5 December 2019
Earlier today, Huawei posted a video on their Weibo account hinting that their upcoming nova 6 5G will be unveiled on 5 December 2019, and it comes with 5G connectivity as well as 105-degree wide-angle selfie camera. But that’s not all, it seems that the selfie camera also comes with a zoom function, which could help in getting that perfect selfie.
Feature-wise, the nova 6 5G comes with new functions in order to help the user take good looking selfies, especially in low-light conditions. In terms of the tech specs, it comes equipped with the HiSilicon Kirin 990 chipset, up to 12GB of RAM, 256GB of ROM, as well as a 6.4-inch display with a pill-shaped notch on the top left.
At the back, the device is expected to come with a 60MP + 16MP + 2MP + 2MP rear camera while the front houses a 32MP + 12MP selfie camera. As for the battery, it should come with a 4000mAh battery which supports 40W fast charging.
With all that said, would you be interested in getting the nova 6 5G as soon as it is available in Malaysia? Let us know on our Facebook page and for more updates such as the Malaysia release date as well as local pricing, stay tuned to TechNave.com.