Party Location
问题描述 :
After the programming contest, all of the contestants would like to throw a party. After the party, however, it will be late, and the contestants will be too tired to walk a long way home. In particular, each contestant refuses to come to the party if it is more than 2.5 km from his or her house.
The solution is to hold the party as close to as many of the contestants’ houses as possible. This is where you come in: your job is to determine the optimal location for the party, so that as many contestants as possible will be willing to attend it.
The solution is to hold the party as close to as many of the contestants’ houses as possible. This is where you come in: your job is to determine the optimal location for the party, so that as many contestants as possible will be willing to attend it.
We consider the city to be a flat square, 50 km on each side. A contestant can walk directly from the party in a straight line to his or her house (there are no obstacles).
输入:
Input consists of a number of cases.
For each case, first there is a positive number N, which means the number of the contestants, and then N lines following, each line containing two floating point numbers indicating the (x,y) coordinates of the house of one of the contestants. Each coordinate is between 0.0 and 50.0 (km). Each house is at a distinct location. There are at most 200 contestants.
For each case, first there is a positive number N, which means the number of the contestants, and then N lines following, each line containing two floating point numbers indicating the (x,y) coordinates of the house of one of the contestants. Each coordinate is between 0.0 and 50.0 (km). Each house is at a distinct location. There are at most 200 contestants.
输出:
Input consists of a number of cases.
For each case, first there is a positive number N, which means the number of the contestants, and then N lines following, each line containing two floating point numbers indicating the (x,y) coordinates of the house of one of the contestants. Each coordinate is between 0.0 and 50.0 (km). Each house is at a distinct location. There are at most 200 contestants.
For each case, first there is a positive number N, which means the number of the contestants, and then N lines following, each line containing two floating point numbers indicating the (x,y) coordinates of the house of one of the contestants. Each coordinate is between 0.0 and 50.0 (km). Each house is at a distinct location. There are at most 200 contestants.
样例输入:
8 4.0 4.0 4.0 5.0 5.0 6.0 1.0 20.0 1.0 21.0 1.0 22.0 1.0 25.0 1.0 26.0
样例输出:
4
题意：已知n（n<=200）位参赛选手的住所坐标，现要邀请尽可能多的选手来参加一个party，而每个选手对于离住所超过2.5Km的party一律不去，求最多可以有多少个选手去参加party。
思路：
不妨先考虑party可能的位置，要尽可能多的邀请到选手参加，则只需考虑party所在位置在某两位住所连线的中点上或某选手住所所在位置，因为这是最大参加party选手数很有可能在的位置。
若其他位置能得到最大参加选手数，那么中点或选手住所也一定可得到。//反证法可得，试着画画就ok~
那么，只要我们枚举所有中点与选手住所的位置，所能得到的可参加party选手数，取其最大值即是答案。
AC code：
/* * @author Novicer * language : C++/C */ #include<iostream> #include<sstream> #include<fstream> #include<vector> #include<list> #include<deque> #include<queue> #include<stack> #include<map> #include<set> #include<bitset> #include<algorithm> #include<cstdio> #include<cstdlib> #include<cstring> #include<cctype> #include<cmath> #include<ctime> #include<iomanip> using namespace std; const double eps(1e-8); typedef long long lint; const int maxn = 200 +5; pair<double,double>con[maxn]; int main(){ // freopen("input.txt","r",stdin); int n; while(cin >> n){ for(int i = 1 ; i <= n ; i++) scanf("%lf%lf",&con[i].first,&con[i].second); int ans = 0; for(int i = 1 ; i <= n ; i++){ // cout << con[i].first << " " << con[i].second << endl; for(int j = 1 ; j <= n ; j++){ pair<double,double> t; t.first = (con[i].first + con[j].first) / 2.0; t.second = (con[i].second + con[j].second) / 2.0; // cout << t.first << " " << t.second << endl; int cnt = 0; for(int k = 1 ; k <= n ; k++){ double dis = pow(t.first - con[k].first,2) + pow(t.second - con[k].second,2); // cout << dis << endl; if(dis <= 6.25 + eps) cnt++; } ans = max(ans , cnt); } } cout << ans << endl; } return 0; }
版权声明：博主表示授权一切转载啦，不过要写上原作者哦：）
参考：http://blog.csdn.net/qq_15714857/article/details/47060439
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懶懶的午後。。。
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，
我也可以拿朝鲜最好的与韩国最差的比，你看人家朝鲜没有色 情、没有毒品、没有垃圾食品，


A nonmagical wall of solid stone springs into existence at a point you choose within range. The wall is 6 inches thick and is composed of ten 10-foot-by-10-foot panels.
Each panel must be contiguous with at least one other panel. Alternatively, you can create 10-foot-by-20-foot panels that are only 3 inches thick.
If the wall cuts through a creature's space when it appears, the creature is pushed to one side of the wall (your choice). If a creature w ould be surrounded on all sides by the wall (or the wall and another solid surface), that creature can make a Dexterity saving throw. On a success, it can use its reaction to move up to its speed so that it is no longer enclosed by the wall.
The wall can have any shape you desire, though it can't occupy the same space as a creature or object.
The wall doesn't need to be vertical or rest on any firm foundation. It must, however, merge with and be solidly supported by existing stone. Thus, you can use this spell to bridge a chasm or create a ramp.
If you create a span greater than 20 feet in length, you must halve the size of each panel to create supports.
You can crudely shape the wall to create crenellations, battlements, and so on.
The wall is an object made of stone that can be damaged and thus breached. Each panel has AC 15 and 30 hit points per inch of thickness. Reducing a panel to 0 hit points destroys it and might cause connected panels to collapse at the DM's discretion.
If you maintain your concentration on this spell for its whole duration, the wall becomes permanent and can't be dispelled. Otherwise, the wall disappears when the spell ends.


--- layout: post title: Friends in 2009 date: 2010-01-02 07:49:39.000000000 -08:00 type: post parent_id: "0" published: true password: "" status: publish categories: [] tags: - "2009" - Graphs meta: _edit_last: "1" tmac_last_id: "166390237654818817" _jetpack_related_posts_cache: a:1:{s:32:"8f6677c9d6b0f903e98ad32ec61f8deb";a:2:{s:7:"expires";i:1542465807;s:7:"payload";a:3:{i:0;a:1:{s:2:"id";i:35;}i:1;a:1:{s:2:"id";i:1313;}i:2;a:1:{s:2:"id";i:1327;}}}} author: login: Philihp email<EMAIL_ADDRESS>display_name: Philihp first_name: "" last_name: "" ---
Lots of differences between now and last year. It's interesting that now that I'm single, a good percentage of my 10 closest friends are also single. The age distribution is a lot wider now too, I expect this trend to continue as I am no longer meeting friends almost exclusively in school.


Roast Coffee House
Photoshop to Web
Roast Coffee House was a site designed and developed as part of the curriculum of the
Skillcrush
Visual Designer Blueprint.
The site was developed mobile first and is
responsive. Flexbox was utilized to ensure the main page logo remained centered and Parallax
scrolling was added for visual interest.


NANO(1) NANO(1) NAME nano - Nano's ANOther editor, an enhanced free Pico clone SYNOPSIS nano [OPTIONS] [[+LINE,COLUMN] FILE]... DESCRIPTION This manual page briefly documents the nano command. nano is a small, free and friendly editor which aims to replace Pico, the default editor included in the non-free Pine package. Rather than just copying Pico's look and feel, nano also implements some missing (or dis‐ abled by default) features in Pico, such as "search and replace" and "go to line and column number". OPTIONS +LINE,COLUMN Places cursor at line number LINE and column number COLUMN (at least one of which must be specified) on startup, instead of the default of line 1, column 1. -? Same as -h (--help). -A (--smarthome) Make the Home key smarter. When Home is pressed anywhere but at the very beginning of non-whitespace characters on a line, the cursor will jump to that beginning (either forwards or backwards). If the cursor is already at that position, it will jump to the true beginning of the line. -B (--backup) When saving a file, back up the previous version of it to the cur‐ rent filename suffixed with a ~. -C dir (--backupdir=dir) Set the directory where nano puts unique backup files if file backups are enabled. -D (--boldtext) Use bold text instead of reverse video text. -E (--tabstospaces) Convert typed tabs to spaces. -F (--multibuffer) Enable multiple file buffers, if available. -H (--historylog) Log search and replace strings to ~/.nano_history, so they can be retrieved in later sessions, if nanorc support is available. -I (--ignorercfiles) Don't look at SYSCONFDIR/nanorc or ~/.nanorc, if nanorc support is available. -K (--rebindkeypad) Interpret the numeric keypad keys so that they all work properly. You should only need to use this option if they don't, as mouse support won't work properly with this option enabled. -L (--nonewlines) Don't add newlines to the ends of files. -N (--noconvert) Disable automatic conversion of files from DOS/Mac format. -O (--morespace) Use the blank line below the titlebar as extra editing space. -Q str (--quotestr=str) Set the quoting string for justifying. The default is "^([ \t]*[#:>\|}])+" if extended regular expression support is available, or "> " otherwise. Note that \t stands for a Tab. -R (--restricted) Restricted mode: don't read or write to any file not specified on the command line; read any nanorc files; allow suspending; allow a file to be appended to, prepended to, or saved under a different name if it already has one; or use backup files or spell checking. Also accessible by invoking nano with any name beginning with 'r' (e.g. "rnano"). -S (--smooth) Enable smooth scrolling. Text will scroll line-by-line, instead of the usual chunk-by-chunk behavior. -T cols (--tabsize=cols) Set the size (width) of a tab to cols columns. The value of cols must be greater than 0. The default value is 8. -U (--quickblank) Do quick statusbar blanking. Statusbar messages will disappear after 1 keystroke instead of 25. Note that -c overrides this. -V (--version) Show the current version number and exit. -W (--wordbounds) Detect word boundaries more accurately by treating punctuation characters as part of a word. -Y str (--syntax=str) Specify a specific syntax highlighting from the nanorc to use, if available. -c (--const) Constantly show the cursor position. Note that this overrides -U. -d (--rebinddelete) Interpret the Delete key differently so that both Backspace and Delete work properly. You should only need to use this option if Backspace acts like Delete on your system. -h (--help) Show a summary of command line options and exit. -i (--autoindent) Indent new lines to the previous line's indentation. Useful when editing source code. -k (--cut) Enable cut from cursor to end of line. -l (--nofollow) If the file being edited is a symbolic link, replace the link with a new file instead of following it. Good for editing files in /tmp, perhaps? -m (--mouse) Enable mouse support, if available for your system. When enabled, mouse clicks can be used to place the cursor, set the mark (with a double click), and execute shortcuts. The mouse will work in the X Window System, and on the console when gpm is running. -o dir (--operatingdir=dir) Set operating directory. Makes nano set up something similar to a chroot. -p (--preserve) Preserve the XON and XOFF sequences (^Q and ^S) so they will be caught by the terminal. -q (--quiet) Do not report errors in the nanorc file and ask them to be acknowledged by pressing Enter at startup. -r cols (--fill=cols) Wrap lines at column cols. If this value is 0 or less, wrapping will occur at the width of the screen less cols columns, allowing the wrap point to vary along with the width of the screen if the screen is resized. The default value is -8. -s prog (--speller=prog) Enable alternative spell checker command. -t (--tempfile) Always save changed buffer without prompting. Same as Pico's -t option. -u (--undo) Enable experimental generic-purpose undo code. By default, the undo and redo shortcuts are Meta-U and Meta-E, respectively. -v (--view) View file (read only) mode. -w (--nowrap) Disable wrapping of long lines. -x (--nohelp) Disable help screen at bottom of editor. -z (--suspend) Enable suspend ability. -$ (--softwrap) Enable 'soft wrapping'. nano will attempt to display the entire contents of a line, even if it is longer than the screen width. Since '$' normally refers to a variable in the Unix shell, you should specify this option last when using other options (e.g. 'nano -wS$') or pass it separately (e.g. 'nano -wS -$'). -a, -b, -e, -f, -g, -j Ignored, for compatibility with Pico. INITIALIZATION FILE nano will read initialization files in the following order: SYSCONFDIR/nanorc, then ~/.nanorc. Please see nanorc(5) and the example file nanorc.sample, both of which should be provided with nano. NOTES If no alternative spell checker command is specified on the command line or in one of the nanorc files, nano will check the SPELL environment variable for one. In some cases nano will try to dump the buffer into an emergency file. This will happen mainly if nano receives a SIGHUP or SIGTERM or runs out of memory. It will write the buffer into a file named nano.save if the buffer didn't have a name already, or will add a ".save" suffix to the current filename. If an emergency file with that name already exists in the current directory, it will add ".save" plus a number (e.g. ".save.1") to the current filename in order to make it unique. In multibuffer mode, nano will write all the open buffers to their respective emergency files. BUGS Please send any comments or bug reports to<EMAIL_ADDRESS>The nano mailing list is available from<EMAIL_ADDRESS>To subscribe, email to<EMAIL_ADDRESS>with a subject of "sub‐ scribe". HOMEPAGE http://www.nano-editor.org/ SEE ALSO nanorc(5) /usr/share/doc/nano/ (or equivalent on your system) AUTHOR Chris Allegretta<EMAIL_ADDRESS>et al (see AUTHORS and THANKS for details). This manual page was originally written by Jordi Mallach<EMAIL_ADDRESS>for the Debian system (but may be used by others). November 30, 2009 version 2.2.0 NANO(1)


Table of contents
Foreword
Preface
Chapter 1
Chapter 2
Chapter 3
Glossary
Bibliography
Index
List of illustrations
List of tables
Notes


Octagons
问题描述 :
Below is a picture of an infinite hyperbolic tessellation of octagons. If we think of this as a graph of vertices (of degree three), then there exists an isomorphism of the graph which maps any vertex x onto any other vertex y. Every edge is given a label from the set {a,b,c} in such a way that every vertex has all three types of edges incident on it, and the labels alternate around each octagon. Part of this labeling is illustrated in the diagram.
So a path in this graph (starting from any vertex) can be specified by a sequence of edge labels. Your job is to write a program which, given a squence of labels such as "abcbcbcabcaccabb", returns "closed" if the path ends on the same vertex where it starts, and returns "open" otherwise.
输入:
The input will begin with a number Z ≤ 200 on a line by itself. This is followed by Z lines, each of which is a squence of length at least 1 and at most 40 of ‘a’s ‘b’s and ‘c’s.
输出:
The input will begin with a number Z ≤ 200 on a line by itself. This is followed by Z lines, each of which is a squence of length at least 1 and at most 40 of ‘a’s ‘b’s and ‘c’s.
样例输入:
2 abababab abcbcbcbcba
样例输出:
closed open
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那是硫酸铜和铁吧。。。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。
求神开小灶的心态，最后只有幻想自己的是神的代言人了。


Light and fast
Clean & Beautiful Design, HTML5 & CSS3 valid code provide good readability and smooth performance.
Responsive design
Responsive designed and Retina Ready. MyJourney will look perfect on any device you can imagine.
Easy to customize
Optimized and valid code using the latest technologies allows to make changes in the page structure of the template.
So simple, so beautiful
MyJourney HTML template is a landing page with clean structure and beautiful minimalistic design. It can be useful in so many ways, including the most obvious, whis is to Tell a story.
Optimized and valid code using the latest HTML5 and CSS3 technologies allows to make changes in the page structure of the template as it is requared by your needs.
Right here, right now
MyJourney is all about being useful when you need nice and simple way to tell the people about what you’ve seen and felt about something important. Something that really means a lot.
@PixelBuddha long ago
@PixelBuddha long ago
@PixelBuddha long ago


Blaming game?
Most of the keepers(exotic pet keepers/owners) had a quite annoying habit of doing a blaming game, every time I saw an owner posting about his/her pet that something happened terrible or just died, they always blame the owner for what happened or they just swiftly judge the situation based on what they saw on the picture or what they read on the post. they almost forgot to collect the facts and asking for other information. this is now typical and happens a lot. This past few months and just the other day I do encounter a lot of misfortune for my newly purchased slings
P.lugardi(L1) - Just died after a day it was arrived on my place
C.versicolor - Literally dead the time I open the parcel
O.aureotibialis and (from Ornithoctoninae sub family)sp South Mindanao - The sp south is very weak upon removing from the vial and the O.auerotibialis is on death curl
P.subfusca (lowland) - 3 weeks under my care and just died
Causes?
Ofcourse those slings pass away with definitely a reason but some of those reason are out of our control and here’s the sample of what I’m talking about
Heat / Temperature
One of the main cause of the casualty especially here in PH. we all know that a very high temperature is very bad for our pets
Poor Courier Service
This one definitely out of our control since a bad courier service like lost parcel, untrack shipments, delayed arrival of shipments and also reckless staff(usually they just don’t care on what iniside the items if its fragile or not). all of this will result of DAG (Dead Arrival Guarantee)
Weak Individual
Most of us know the famous line of Shishio Makoto from Rurouni Kenshin “The strong shall live and the weak shall die!” unfortunately there’s always a “weak slings” out there because we cannot guarantee that 100% of the evolved from eggs with legs to spiderlings can be called survivors. yes they survived the level 1 to level 2 of their ecdysis cycle but some of the weak individual cannot pass the 3rd level and just literally die for just being “too weak” and the sad part of it is we cannot just identify by our own naked eye the differences between the weak and not.
Still criticize?
Well my point is before do pointing finger, blaming and cursing others make sure you have enough evidence, information and consider the facts and possibilities of why the disaster happens. We also have to understand that sometimes its out of our control
PEACE! (^_^)


- Structure and Interpretation of Computer Programs
I'm going to try to convince you that data is code. Strap yourselves in!
A cons cell is a way of representing a
pair, and it has two operations, car
and
cdr
, to access the first and
second elements of the pair respectively. In Python, we could construct and
access cons cells as follows:
cons = lambda a: lambda b: (a, b)
car = lambda cell: cell[0]
cdr = lambda cell: cell[1]
Let's create a pair and get the second element:
>>> p = cons(1)(cons(2)(()))
>>> car(cdr(p))
2
It turns out that cons cells are all you need to implement singly linked lists.
For example, lists in Lisp are implemented as a series of nested cons cells. A
list is either empty (represented above by ()
) or a cons cell where the first
element of the pair is the head of the list and the second element of the pair
is the rest of the list. Using our above definitions in Python, the list [0,
1, 2, 3]
would be represented as (0, (1, (2, (3, ())))). In code, this would
be:
cons(0)(cons(1)(cons(2)(cons(3)(()))))
One way of visualising the above list is as follows:
cons
/ \
0 cons
/ \
1 cons
/ \
2 cons
/ \
3 ()
Suppose we wanted to access the second element of this list. We could express
this as the car
of the cdr
of this list. In code:
>>> example = cons(0)(cons(1)(cons(2)(cons(3)(()))))
>>> car(cdr(example))
1
So far we've defined functions that wrap Python's tuples, and we're still in data land, working with those tuples. But it doesn't have to be this way.
You may have noticed that my definitions above were all functions of one argument. This was not entirely coincidental: cons cells as described above are very similar to Church pairs, which are a way of representing pairs in the lambda calculus. Let's make a minor change to the above definitions:
pair = lambda a: lambda b: lambda f: f(a)(b)
fst = lambda p: p(lambda a: lambda b: a)
snd = lambda p: p(lambda a: lambda b: b)
nil = lambda a: a
We can recreate the pair above:
>>> p = pair(1)(pair(2)(nil))
>>> fst(snd(p))
2
Our pair p
is now a function, but it is representing the same data as above.
As an aside, the functions we use in fst
and snd
are Church
booleans that
encode true
and false
in the lambda calculus. We can rewrite our definitions
with this new knowledge:
true = lambda a: lambda b: a
false = lambda a: lambda b: b
fst = lambda p: p(true)
snd = lambda p: p(false)
We can perform the same operations as before to get the second element of our list:
>>> example = pair(0)(pair(1)(pair(2)(pair(3)(nil))))
>>> fst(snd(example))
1
Now we've moved to function land, and there are no tuples in sight. All we need are functions of one argument, which is convenient because this is all that lambda calculus gives us. Fortunately, lambda calculus is Turing complete and therefore enough.
Our code is represented as bits in memory i.e. data, but our data can be represented as functions i.e. code. You might say that bits and bytes are the lowest level representation and therefore somehow more fundamental than code, but even our data is just an undistinguished pattern of 1s and 0s without some code to make sense of it. It really is turtles all the way down.
There are much more comprehensive treatments of this material available online. I'm aware of Matt Might's and James Tauber's.
Many thanks to Andy Lee, Juan Soto, and Sarah Ransohoff for their excellent feedback on on this post.
Comments !


Account
Account
Name :
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Email :
{{user.email}}
Phone :
{{user.phone}}
Shop
Shop name :
{{shop.name}} ({{shop.shopcode}})
Address :
{{shop.address.address}}, {{shop.address.subdistrict}}, {{shop.address.district}}, {{shop.address.province}}, {{shop.address.postcode}}
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Get updates on speakers, offers and a reminder when we make our mental health in the workplace white paper available.
We won’t share your email address with anyone else and will only contact you about the summit.
Mon 30 March 2020 08:15–17:30
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Rule base class.
See Also: Inherited members from object.
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Initializes a new instance of this class with XML file. | |
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Initializes a new instance of this class. |
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AddVariable
(Variable)Adds a variable to this rulebase. |
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DeclareFacts
()Declares the facts in this rulebase. |
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ForwardChain
()Starts the forward chain. |
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GetConflictList
(bool)Returns the list of the conflicting rules. |
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GetVariable
(string)Returns the variable having given name. |
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GetVariableValue
(string)Returns the value of the variable. |
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NewFact
(Variable, object)Creates a new fact and add it to this rulebase. |
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NewRule
(string)Creates a new rule and adds it to this rulebase. |
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NewRule
(Clause, Consequent)Creates a new rule and adds it to this rulebase. |
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NewRule
(Clause[], Consequent)Creates a new rule and adds it to this rulebase. |
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NewRule
(string, Clause, Consequent)Creates a new rule and adds it to this rulebase. |
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NewRule
(string, Clause[], Consequent)Creates a new rule and adds it to this rulebase. |
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PrintRules
()Writes the rules in this rule base to the console. |
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PrintVariables
()Writes the variables of this rule base to the console. |
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Reset
()Resets variables, rules and facts in this rule base. |
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SelectRule
(List<Rule>)Returns the rule having the most antecedents. |
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SetVariableValue
(string, string)Sets the value of the variable. |
Initializes a new instance of this class with XML file.Syntax
public RuleBase (System.IO.Stream stream)Parameters
- stream
- The stream of the rule written in XML.
Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Initializes a new instance of this class.Syntax
public RuleBase (string name)Parameters
- name
- The name of this rule base.
Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Adds a variable to this rulebase.Syntax
Parameters
- variable
- The variable to be added.
Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Declares the facts in this rulebase.Syntax
public void DeclareFacts ()Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Starts the forward chain.Syntax
public void ForwardChain ()Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Returns the list of the conflicting rules.Syntax
public List<Rule> GetConflictList (bool test)Parameters
- test
- Whether do or do not test the rules.
Returns
The list of the conflicting rules.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Returns the variable having given name.Syntax
Parameters
- name
- The name of the variable.
Returns
The variable having given name.Remarks
If existing variable is not found, creates a new one.Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Returns the value of the variable.Syntax
Parameters
- name
- The name of the variable.
Returns
The value of the variable.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
The name of this rule base.Syntax
public string Name { get; set; }Value
The name in string.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Creates a new fact and add it to this rulebase.Syntax
Parameters
- lhs
- Left hand side of the new fact.
- rhs
- Right hand side of the new fact.
Returns
The new fact.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Creates a new rule and adds it to this rulebase.Syntax
Parameters
- ruleName
- The name of the new rule.
Returns
The new rule.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Creates a new rule and adds it to this rulebase.Syntax
Parameters
- antecedent
- The antecedent of the new rule.
- consequent
- The consequent of the new rule.
Returns
The new rule.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Creates a new rule and adds it to this rulebase.Syntax
Parameters
- antecedents
- The antecedents of the new rule.
- consequent
- The consequent of the new rule.
Returns
The new rule.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Creates a new rule and adds it to this rulebase.Syntax
Parameters
- ruleName
- The name of the new rule.
- antecedent
- The antecedent of the new rule.
- consequent
- The consequent of the new rule.
Returns
The new rule.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Creates a new rule and adds it to this rulebase.Syntax
Parameters
- ruleName
- The name of the new rule.
- antecedents
- The antecedents of the new rule.
- consequent
- The consequent of the new rule.
Returns
The new rule.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Writes the rules in this rule base to the console.Syntax
public void PrintRules ()Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Writes the variables of this rule base to the console.Syntax
public void PrintVariables ()Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Resets variables, rules and facts in this rule base.Syntax
public void Reset ()Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Returns the rule having the most antecedents.Syntax
public Rule SelectRule (List<Rule> ruleList)Parameters
- ruleList
- List of rules.
Returns
The rule having the most antecedents.Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>
Sets the value of the variable.Syntax
Parameters
- name
- The name of the variable.
- value
- The value of the variable.
Remarks
Requirements
Namespace: RuleBaseSystem
Assembly: RuleBaseSystem (in RuleBaseSystem.dll)
Assembly Versions: <IP_ADDRESS>


| Name | Size | Time | |||
|---|---|---|---|---|---|
| The directory is empty. |
Please wait while we check the validity of your Upspin account and check connectivity to your directory server.
To use Upspin you must register a user name and public key with the central key server.
Your user name is how the Upspin system and its users will identify you and your data. A user name is just an email address you own during signup. The email address itself is not used by Upspin after signup; it doesn't matter if you lose or delete it later.
An Upspin key pair was generated for you and stored in this directory on your local machine:
This key pair provides access to your Upspin identity and data. If you lose the keys you can re-create them using this "secret seed":
Write this down and store it in a secure, private place. Do not share your secret key or this string with anyone. If you lose your key and its secret seed you will lose access to this Upspin identity, including all the data you have stored and even the ability to use your registered user name.
The Upspin key server has sent an email to to verify your ownership of that address.
To complete the signup process, find that email, click the verification link, and then click the 'Proceed' button.
To store data in Upspin you need directory and store servers. You may nominate existing servers or deploy them yourself. Alternately, if you do not want to write data to Upspin you can skip this step.
Specify the host names of your Upspin directory and store servers. Ask your Upspin server administrator if you don't know what this means.
To deploy an Upspin server to the Google Cloud Platform, follow these steps:
Choose a name for the Google Cloud Storage Bucket that will hold your Upspin data.
This name must be globally unique, so we suggest using your Project ID as a prefix.
Choose the geographical locations of your Storage Bucket and Compute Instance. For best performance these should be close to the users of your Upspin server.
See the documentation to learn about Bucket Locations. (Note that "Regional" storage is cheaper than "Multi-regional" storage.)
See the documentation to learn about Regions and Zones.
Every Upspin server runs as its own Upspin user. We will create a user derived from your user name, with the addition of a suffix.
Specify a user name suffix for your Upspin server user. The user name with suffix need not be a valid email address; your Upspin user may register any number of "suffixed" users without email verification.An Upspin key pair was generated for the server user and stored in this directory on your local machine:
This key pair provides access to your server's Upspin identity and data. If you lose the keys you can re-create them using this "secret seed":
Write this down and store it in a secure, private place. Do not share your secret key or this string with anyone.
Your Upspin server is running on a virtual machine with the IP address .
Specify a host name for your Upspin server. This name is not user-visible, appearing only in your key server record, configuration file, and in the metadata for all Upspin content you write.
If you wish to use a host name under a domain you control, create a DNS A record for that host name that points to and specify the host name in the field below.
Otherwise, you may leave the field blank to use a default host name provided for you under the domain upspin.services.
You have nominated the host name for use with your Upspin server. Make sure you have set up a DNS "A record" that points that host name to .
You opted to use a default host name (provided by the Upspin project) for your Upspin server. The assigned name is . You need not write this down; it will be stored in your key server record and configuration file.
Wait a few minutes for the changes to propagate through the DNS system before clicking 'Continue'. (Please be patient; this can sometimes take up to an hour.)
Your Upspin server is configured to allow writes by your user and the server user. If you would like to allow other users to store their directory trees and content in your Upspin server, add them to this list:
Congratulations. You've successfully created an Upspin account and tree. What's next?
Some suggestions:
| Name | |
|---|---|
| Size | |
| Time | |
| Attributes | |
| Writer |
Recursively these paths:
to this directory:


Provide contextual feedback messages for typical user actions with the handful of available and flexible alert messages.


Fixed Navbar
Home
About
Pricing
Support
Field Service
Tech Support
Create Ticket
Contact
Content Here


{% set projects = PROJECT_DATA[SERIES] %} {% extends "templates/base.tmpl" %} {% block pagetitle %}{{SERIES_TITLE}} Administrator Guides{% endblock %} {% block title %} Documentation > Administrator Guides {% endblock %} {% block content %}
This page contains documentation about administering OpenStack services.
{{project.service}}
{% endif %} {%- endfor %}Documentation treated like code, powered by the community - interested?
How To Contribute


|
Elektra
0.9.3
|
The kdb tool allows users to interact with Elektra’s Key Database via the command line. This tutorial explains the export function of kdb. This command lets you export Keys from the Elektra Key Database.
The command to use kdb export is:
In this command, source is the root key of which Keys should be exported. For instance, kdb export system/export
would export all the keys below system/export
. Additionally, this command exports keys under the system/elektra
directory by default. It does this so that information about the keys stored under this directory will be included if the Keys are later imported into an Elektra Key Database. This command exports keys to stdout
to store them into the Elektra Key Database. Typically, the export command is used with redirection to write the Keys to a file.
The format argument can be a very powerful option to use with kdb export. The format argument allows a user to specify which plugin is used to export the keys from the key database. The user can specify any storage plugin to serve as the format for the exported Keys. For instance, if a user mounted their hosts file to system/hosts
using kdb mount /etc/hosts system/hosts hosts
, they would be able to export these keys using the hosts format by using the command kdb export system/hosts hosts > hosts.ecf
. This command would essentially create a backup of their current /etc/hosts
file in a valid format for /etc/hosts
.
If no format is specified, the format dump
will be used instead. The dump format is the standard way of expressing keys and all their relevant information. This format is intended to be used only within Elektra. The dump format is a good means of backing up Keys from the key database for use with Elektra later such as reimporting them later. As of this writing, dump
is the only way to fully preserve all parts of the KeySet
.
The kdb export command takes one special option: -E
or alternatively --without-elektra
, which tells kdb
to omit the system/elektra
directory of keys.
This command would export all keys stored under system/backup
, along with relevant keys in system/elektra
, into a file called backup.ecf
.


Hong Kong Court declares mask ban excessive, unconstitutional
Hong Kong: A British colonial-era emergency law revived by Hong Kong’s government to ban masks in the ongoing protests was on Monday ruled by the High Court to be excessive and unconstitutional. The court said that the law, which came into effect on October 5, goes against the Basic Law (the city’s constitution), Efe news reported citing public broadcaster Radio Television Hong Kong as saying. “We should also make it clear that it is not our judgment that (an) ‘anti mask’ law is generally objectionable or unconstitutional. Its validity must, however, depend on the details of the legislation and the particular societal aims sought to be pursued by the measure,” the court’s judges said. (IANS)
Also Read: Key highway reopens, Hong Kong remains relatively Calm
Also Watch: MOU signed between Marwari Hospitals and Delhi’s Sir Ganga Ram Hospital in Guwahati


Ruby-PHP is particularly well suited for organizing and transporting huge sets of information. For that reason PHP is the server-side language for 82.5% of all websites whose server-side language is known.
In this course we'll focus on the fundamentals of programming web applications using PHP and the web framework Silex. Working with PHP and Silex, we'll use the MVC pattern of web development, where a program's core logic is written in its models (PHP classes). The user interface is coded in views (HTML/CSS/JavaScript). And controllers (Silex) will handle web requests, defining what model code to run and which views (Twig templates) to return back in the HTTP response.
In this course we focus on the fundamentals of programming web applications using Java and the web framework Spark. Working with Java and Spark, we'll use the MVC pattern of web development, where a program's core logic is written in its models (Java classes). The user interface is coded in views (HTML/CSS/JavaScript). And controllers (Spark) will handle web requests, defining what model code to run and which views to return back in the HTTP response. Also, we'll learn how to build Android apps, including how to create user interfaces, communicate with a backend server, and take advantage of device features.
Welcome to CSS! You are about to set sail on 5 weeks of Cascading Style Sheets to bring beauty and excitement to the web pages that you create.
Welcome to C#! You are about to begin your journey into the world of web development in the C# programming language.C# is the object-oriented component of the ASP.NET Framework. Microsoft Chief Architect and C# team leader Anders Hejlsberg described it as an iteration and improvement of the C++ language. Hejlsberg touted C# as "the first component-oriented language in the C/C++ family." As a result, it is " a simple, modern, general-purpose, object-oriented programming language" and to be "economical with regard to memory and processing power requirements
Welcome to Epicodus  . Thank you so much for spending time and answering the questions. Based on the answers, we can suggest you Java/Android or CSS design.
Please, meet us at location : 400 SW 6th Ave #800, Portland, OR 97204
Try next time!!!
Epicodus is the most affordable full-time, in-person code school, and one of the few programs that includes an internship with a tech company as well as job search support. Students graduate with real-life work experience already on their resumes, a dedicated team to help land their first job, and a close community of peers and instructors supporting them along the way.


{% extends 'base.html' %} {% from 'navigation.njk' import navbar %} {% block navigation %} {{ navbar('cfp') }} {% endblock %} {% block main %}
Authors are encouraged to submit their papers (6-8 pages) in Russian or English language via the online registration system website at https://dccn.ru/. The accepted papers will be published in the Conference Proceedings volume (included into the Russian Science Citation Index) prior to the beginning of the Conference. After a peer review and plagiarism check using IEEE CrossCheck, authors of selected submissions in English, recommended by the Program Committee, will be invited to submit their extended papers (12-15 pages in Springer LNCS template). After a second round of review the accepted extended papers will be published by Springer (approved) as a stand-alone volume of selected extended papers (indexed in Scopus and Web of Science).
Topics include, but are not limited to the following fields:
You can download the LaTeX templates via the following links:
Authors of selected extended submissions in English, recommended by the Program Committee to be included into the Springer volume, should consult Springer's authors' guidelines and Springer's proceedings LaTeX template for the preparation of their papers. Springer encourages authors to include their ORCIDs in their papers. In addition, the corresponding author of each paper, acting on behalf of all of the authors of that paper, must complete and sign a Consent-to-Publish form, through which the copyright for their paper is transferred to Springer.


|
Little Heroes
|
This script can be used to anchor an object to the side or corner of the screen, panel, or a widget. More...
Public Types | |
| enum | Side { Side.BottomLeft, Side.Left, Side.TopLeft, Side.Top, Side.TopRight, Side.Right, Side.BottomRight, Side.Bottom, Side.Center } |
Public Attributes | |
| Camera | uiCamera = null |
| Camera used to determine the anchor bounds. More... | |
| GameObject | container = null |
| Object used to determine the container's bounds. More... | |
| Side | side = Side.Center |
| Side or corner to anchor to. More... | |
| bool | runOnlyOnce = true |
| If set to 'true', UIAnchor will execute once, then will be disabled. More... | |
| Vector2 | relativeOffset = Vector2.zero |
| Relative offset value, if any. More... | |
| Vector2 | pixelOffset = Vector2.zero |
| Pixel offset value if any. More... | |
This script can be used to anchor an object to the side or corner of the screen, panel, or a widget.
| enum UIAnchor.Side |
| GameObject UIAnchor.container = null |
Object used to determine the container's bounds.
Overwrites the camera-based anchoring if the value was specified.
| Vector2 UIAnchor.pixelOffset = Vector2.zero |
Pixel offset value if any.
For example "10" in x will move the widget 10 pixels to the right while "-10" in x is 10 pixels to the left based on the pixel values set in UIRoot.
| Vector2 UIAnchor.relativeOffset = Vector2.zero |
Relative offset value, if any.
For example "0.25" with 'side' set to Left, means 25% from the left side.
| bool UIAnchor.runOnlyOnce = true |
If set to 'true', UIAnchor will execute once, then will be disabled.
Screen size changes will still cause the anchor to update itself, even if it's disabled.
| Side UIAnchor.side = Side.Center |
Side or corner to anchor to.
| Camera UIAnchor.uiCamera = null |
Camera used to determine the anchor bounds.
Set automatically if none was specified.


Collection
Statistics on the participation and achievement of pupils taking the 14 to 19 diploma qualification.
Statistics from May 2010 onwards are available on GOV.UK. You can find our archived statistics on the National Archives . Note: the search function is not available on archived content so please use the filters on the left of each page.


Name:
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Bio:
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Organization:
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Joined on:
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Email:
{{getUserInfo.email}}
Location:
{{getUserInfo.location}}
Total number of contributions in the last year:
{{listOfReposContributedTo.total}}


API:
Choose here
javascript free with single page
javascript free with multi page using xpath
javascript free with multi page using url
javascript with single page
javascript with multi page using xpath
URL:
Xpath of list:
Xpath of next page:
delay:
{{link}}


SIT Study Abroad offers extraordinary experiential education to undergraduate students on semester and summer programs in over 30 countries in Africa, Asia and the Pacific, Europe, Latin America, and the Middle East, as well as comparative programs in multiple locations. SIT students benefit from high levels of access to the extensive networks of experts and community members that enrich each program, immersing themselves in the language, culture, and key issues ranging from human rights to migration to environmental change. They get direct, field-based experience from their highly qualified instructors as well as the invaluable exposure and access to local culture within their host communities.
The International Honors Program (IHP), founded in 1958, invites students to examine a critical global issue on a global comparative level. As such, students are able to explore key topics — such as health and community, climate change, 21st century cities, social entrepreneurship and food security — in four contrasting countries, beginning in the US.
Gregory Barber Jr. knows his purpose in life is to be a healer. Growing up in the College Park area of Atlanta, Georgia, he often watched people either give up their lives to the streets or never reach their full potential.
“Through my mother, an educator, and my father, a janitor, I was instilled with the belief that I can maximize my full potential through a life dedicated to the service of others,” said the 20-year-old Morehouse College junior, who is double majoring in psychology and African American studies and is this year’s recipient of the Robert Kantor Scholarship.
Currently studying with SIT Study Abroad, Gregory is in Uganda and Rwanda working on an Independent Study Project that examines the impact of the Rwandan genocide on orphaned children and evaluates the different mechanisms used to help them cope with trauma. He wants to apply these best practices when he returns home to help children who have lost a parent either through death, divorce, incarceration, or violence.
Gregory is grateful for the generous support of the donors, a 1997 SIT Study Abroad Brazil participant and his wife, who established the Robert Kantor Scholarship to honor a family member.
Gregory’s first-ever trip overseas also honors another family member. His mother passed away on June 22, 2012 after a 16-year struggle with systemic lupus erythematosus. Gregory was just one month shy of his seventeenth birthday and senior year of high school. Her death created a financial strain that almost derailed his plans to go to college and study abroad. The Bonner Scholars Program at Morehouse College and SIT’s Robert Kantor Scholarship put him back on track for both.
Upon completing his undergraduate degree at Morehouse College, Gregory plans to attain a doctorate in developmental psychology and wants to focus his research on maladaptive development processes, particularly in children affected by traumatic events.
In the meantime, he is adjusting nicely to his new home in Africa, and describes it as beautiful, warm and hospitable. He is enjoying living with his host family and being fully immersed in a new culture.
“Studying abroad allows you to be more transparent, more accepting and more understanding of different people, different environments and different cultures,” said Gregory. “I cannot even articulate how thankful I am for the opportunity.”
As one of only a few women to become Foreign Service Officers in 1957, Morelle Lasky Levine knows first-hand the importance of international experience to a young person’s career. She served for seven years, holding positions in the U.S. Embassy in Brussels, and was assigned to work on a four -person State Department team coordinating the development of policy for U.S. participation in the newly created Organization for Economic Cooperation and Development (OECD), all before the age of 29.
In the summer of 1954, between her sophomore and junior years at Wellesley College, Morelle traveled to Oaxaca, Mexico, with The Experiment and lived with a family that owned a general store and had seven children ranging in age from 8 to 22 years of age. “Life as part of that family was a fascinating and joyous adventure,” she recalled.
She said The Experiment in International Living had a major impact on her life and career.
“I never again viewed ‘foreigners’ as really foreign, and I came to view close personal contact between people of different nationalities, ethnic groups and religions as the best means of dispelling the mutual suspicion and distrust that creates barriers to peaceful co-existence within and between nations.” — Morelle Lasky Levine
By supporting World Learning’s initiative to expand study abroad opportunities at Historically Black Colleges and Universities (HBCUs), Morelle hopes to give African-American students the chance to gain valuable overseas experience that can help them pursue international careers. A recent summit organized by World Learning with Spelman College was attended by representatives from over 25 of these institutions, the White House, and the U.S. Department of State.
“Despite the fact that higher education is now more available to black students than in the past, the lack of study abroad experience, even by faculty members, is retarding the progress that African-Americans can make professionally compared to their white counterparts” Morelle said. “That, in turn, impedes the role that the U.S. can play in this globalized world.”
By supporting World Learning’s initiative to expand study abroad opportunities at HBCUs, Morelle hopes to give African-American students the chance to gain valuable overseas experience that can help them pursue international careers.
Support for the HBCU Summit is the most recent gift in a long history of significant contributions provided by Morelle, who is a founding donor to The Experiment Leadership Institute and has endowed two scholarships for World Learning, one supporting The Experiment in International Living, and the other in support of SIT Study Abroad. These are just a few highlights of Morelle’s many years of loyal support to World Learning.
World Learning Board Member Paul Muther’s career in international business and finance spans four continents and half a dozen countries. Muther credits his experience on the International Honors Program (IHP) with playing a major role in shaping his desire to live and work with people from other cultures, as well as his commitment to World Learning’s mission and programs.
“It further deepened my interest in seeing other parts of the world and being engaged in them,” Muther explained.
He heard about IHP, then called the International School of America, as junior at Harvard College and thought it was “a really exciting opportunity to go around the world.” On the program, Muther and 13 other students spent the 1965-66 academic year traveling to Tokyo, Hong Kong, New Delhi, Istanbul, Beirut, Rome, Berlin, Warsaw, and Stockholm, living with host families, and studying comparative economic and sociological systems, philosophy and religion.
According to Muther, IHP was an “amazing” experience that expanded his understanding of other people and “the struggles that they have to deal with in their daily lives.” He said living in Japan, Hong Kong, and New Delhi were the most impactful as, at the time, the living conditions in those places were so much different from the United States. Muther also saw firsthand serious issues those societies faced, including the influx of immigrants from mainland China to Hong Kong and poverty in India, and was fascinated to learn about the different approaches each country took to address the challenges of economic development.
After graduating from Harvard, he spent a summer interning in Prague and two and a half years in the Army stationed in Germany, before attending Stanford University where he obtained both JD and MBA degrees. Muther then took a job with The First National Bank of Chicago, where he worked for 30 years in Chicago, London, Sydney, Hong Kong, Seoul, and Toronto.
Muther joined the board of IHP, then an independent organization, in 2004 at the request of William Michaelcheck, then chairman of IHP and now a World Learning trustee. When IHP merged with World Learning in 2010, Muther became a member of the World Learning Board. During his time as a trustee he has served as chair of the Finance Committee, as a member of the Audit and Investment Committees, and participated in Advancement Committee activities. Muther said he enjoys working with the other trustees and contributing to World Learning.
“I believe in the mission and perceive an opportunity to have some influence with achieving its objectives,” he said of his trusteeship. Muther said IHP has been a positive addition to SIT Study Abroad’s portfolio of programs because it provides students with options for their time overseas. He also thinks its “unique” comparative perspective helps students gain a more comprehensive understanding of the program’s themes, which now include global health, human rights, and climate change, among others.
“It offers students the real opportunity to see how different countries or different cultures deal with the core basic issues,” he said.


China accuses Australian media of fabricated allegations of interference
BEIJING (Reuters) - China, responding to allegations of interfering in Australian politics, said it had never tried to meddle in other countries’ internal affairs and wasn’t interested in doing so.
Foreign ministry spokesman Geng Shuang made the comment at a daily press briefing on Monday, adding that certain Australian media outlets have fabricated allegations of interference.
On Sunday, Australia’s “60 Minutes” program and affiliated newspapers said a suspected Chinese espionage ring had offered money to pay for a Melbourne luxury car dealer to run for a seat in Australia’s federal parliament.
The Australian Security Intelligence Organisation said it is investigating an alleged plot by China to install an agent in Australia’s parliament.


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Welcome to TheSweatSpace
The Place to Train, Sweat it Out, and Get Ripped
Home
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Logo:
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Telephone:
+31286554286
Email:
thesweatspace@gym.com


As the size of a knowledge base grows, performance becomes more problematic. The inference engines we have looked at so far use a simple pattern matching algorithm to find the rules to fire. Various indexing schemes can be used to speed up that pattern matching process.
The indexing problem is different for forward and backward chaining systems. Backward chaining systems need to be accessed by the goal pattern in the right hand side of the rule. Forward chaining systems need to be indexed by the more complex patterns on the left hand side. Backward chaining issues will be discussed briefly in this chapter, followed by more in depth treatment of a simplified Rete match algorithm for the Foops forward chaining system.
For performance in backward chaining systems, the rules are indexed by goal patterns on the right hand side. In particular, if the goal is to find a value for a given attribute, then the rules should be indexed by the attribute set in the RHS of the rule. This happens automatically for the pure Prolog rules in the bird identification program since the attributes are Prolog predicate names which are generally accessed through hashing algorithms. The indices, if desired, must be built into the backward chaining engine used in Clam. Some Prologs provide automatic indexing on the first argument of a predicate. This feature could be used to provide the required performance.
Given indexing by the first argument, the rules in Clam would be represented:
rule(Attribute, Val, CF, Name, LHS).
This way, a search for rules providing values for a given attribute would quickly find the appropriate rules.
Without this, each rule could be represented with a functor based on the goal pattern and accessed using the univ (=..) predicate rather than the pattern matching currently used in Clam. The predicates which initially read the rules can store them using this scheme. For example, the internal format of the Clam rules would be:
Attribute(Val, CF, Name, LHS).
In particular, some rules from the car diagnostic system would be:
problem(battery,
100, 'rule 1',
[av(turn_over, no), av(battery_bad, yes)]).
problem(flooded,
80, 'rule 4',
[av(turn_over, yes), av(smell_gas, yes)]).
battery_bad(yes, 50, 'rule 3', [av(radio_weak, yes)]).
When the inference is looking for rules to establish values for an attribute - value pattern, av(A, V), the following code would be used:
Rule =.. [A, V, CF, ID, LHS],
call(Rule),
...
This structure would allow Clam to take advantage of the hashing algorithms built into Prolog for accessing predicates.
OPS5 and some high-end expert system shells use the Rete match algorithm to optimize performance. It is an indexing scheme which allows for rapid matching of changes in working memory with the rules. Previous match information is saved on each cycle, so the system avoids redundant calculations. We will implement a simplified version of the Rete algorithm for Foops.
The Rete algorithm is designed for matching left hand side rule patterns against working storage elements. Let's look at two similar rules from the room placement expert system.
rule f3#
[couch - C with [position-wall/W],
wall - W with [opposite-OW],
tv - TV with [position-none, place_on-floor]]
==>
[update(tv - TV with [position-wall/OW])].
rule f4#
[couch - C with [position-wall/W],
wall - W with [opposite-OW],
tv - TV with [position-none, place_on-table],
end_table - T with [position-none]]
==>
[update(end_table - T with [position-wall/OW]),
update(tv - TV with [position-end_table/T])].
First let's define some terms. Each LHS is composed of one or more frame patterns. An example of a frame pattern is:
tv-TV with [position-none, place_on-table]
The frame pattern will be the basic unit of indexing in the simplified Rete match algorithm. In a full implementation, indexing is carried down to the individual attribute-value pairs within the frame pattern, such as place_on-table.
The match algorithm used in the first implementation of Foops takes every rule and compares it to all the frame instances on each cycle. In particular, both of the example rules above would be compared against working storage on each cycle. Not only is redundant matching being done on each cycle, within each cycle the same frame patterns are being matched twice, once for each rule. Since working memory generally has few changes on each cycle, and since many of the rules have redundant patterns, this approach is very inefficient.
With the Rete algorithm, the status of the match information from one cycle is remembered for the next. The indexing allows the algorithm to update only that match information which is changed due to working memory changes.
The rules are compiled into a network structure where the nodes correspond to the frame patterns in the LHS of the rules. There are three basic types of node which serve as: the entry to the network; the internals of the network; and the exit from the network. These are called root nodes, two-input nodes, and rule nodes respectively.
Figure 8.1. The nodes of the Rete network for two sample rules
The network has links which run from single frame patterns in the root nodes, through the two-input nodes, to full LHS patterns in the rule nodes. Figure 8.1 shows the nodes and links generated from the two sample rules.
The root nodes serve as entry points to the Rete network. They are the simplest patterns recognized by the network, in this case the frame patterns that appear in the various rules. A frame pattern only appears once in a root node even if it is referenced in multiple rules. Each root node has pointers to two-input nodes which are used to combine the patterns into full LHS patterns.
Two-input nodes represent partially completed LHS patterns. The left input has a pattern which has one or more frame patterns as they appear in one or more rules. The right input has a single frame pattern, which when appended to the left input pattern completes more of a full LHS pattern. The two-input node is linked to other two-input or rule nodes whose left input matches the larger pattern.
The rule nodes are the exit points of the Rete network. They have full LHS patterns and RHS patterns.
Associated with each two-input node, are copies of working storage elements which have already matched either side of the node. These are called the left and right memories of the node. In effect, this means working memory is stored in the network itself.
Whenever a frame instance is added, deleted, or updated it is converted to a "token". A token is formed by comparing the frame instance to the root patterns. A root pattern which is unified with the frame instance is a token. The token has an additional element which indicates whether it is to be added to or deleted from the network.
Figure 8.2. The relationship between frame patterns, instances, tokens, and nodes
The token is sent from the root node to its successor nodes. If the token matches a left or right pattern of a two-input successor node, it is added (or deleted) from the the appropriate memory for that node. The token is then combined with each token from the memory on the other side (right or left) and compared with the pattern formed by combining the left and right patterns of the two input node. If there is a match, the new combined token is sent to the successor nodes. This process continues until either a rule is instantiated or there are no more matches.
Figure 8.2 shows the relationships between rules, frame patterns, frame instances, nodes, and tokens. It shows the top portion of the network as shown in Figure 8.1. It assumes that couch-1 with [position-wall/north] already exists in the left memory of two-input node #1. Then the frame instance wall-north with [opposite-south, left-west, right-east] is added, causing the generation of the token wall-north with [opposite-south]. The token updates the right memory of node #1 as shown, and causes a new token to be generated which is sent to node #2, causing an update to its left memory.
Lets trace what happens in the network during selected phases of a run of the room configuration system.
First the walls are placed during initialization. There are four wall frame instances asserted which define opposites and are therefor recognized by the portion of the system we are looking at. They are used to build add-tokens which are sent to the network.
wall-north with [opposite-south].
wall-south with [opposite-north].
wall-east with [opposite-west].
wall-west with [opposite-east].
Each of these tokens matches the following root pattern, binding OW to the various directions:
wall-W with [opposite-OW].
Figure 8.3. The sample network after initialization
Therefore, each token is passed on to the right side of two-input node #1 as indicated by the list of links associated with that root pattern. Each of these terms is stored in the right memory of node #1. Since there is nothing in the left memory of node #1, network processing stops until the next input is received.
Next, the furniture is initialized, with the couch, tv, and end_table placed with position-none. They will be internally numbered 1, 2, and 3. Since the root pattern for couch in the segment we are looking at has a position-wall/W, the couch does not show up in it at this time. However, node #2 and node #4 have their right memories updated respectively with the tokens:
tv-2 with [position-none, place_on-floor].
end_table-3 with [position-none].
At this point the system looks like figure 8.3. The shaded boxes correspond to the two-input nodes of figure 8.1.
After initialization, the system starts to fire rules. One of the early rules in the system will lead to the placing of the couch against a wall, for example the north wall. This update will cause the removal of the token couch-1 with [position-none] from parts of the network not shown in the diagrams, and the addition of the token couch-1 with [position-wall/north] to the left memory of node #1 as shown in figure 8.4. This causes a cascading update of various left memories as shown in the rest of figure 8.4 and described below.
Node #1 now has both left and right memories filled in, so the system tries to combine the one new memory term with the four right memory terms. There is one successful combination with the wall-north token, so a new token is built from the two and passed to the two successor nodes of node #1. The new token is:
[couch-1 with [position-wall/north],
wall-north with [opposite-south] ]
This token is stored in the left memories of both successors, node #2 and node #3. There is no right memory in node #3, so nothing more happens there, but there is right memory in node #2 which does match the input token. Therefor a new token is constructed and sent to the successor of node #2. The new token is:
[couch-1 with [position-wall/north],
wall-north with [opposite-south],
tv-2 with [position-none, place_on-floor] ]
The token is sent to the successor which is rule #f3. The token is the binding of the left side of the rule, and leads to variable bindings on the right side of the rule. This is a full instantiation of the rule and is added to the conflict set. When the rule is fired, the action on the right side causes the position of the tv to be updated.
update ( tv-2 with [position-wall/south] )
Figure 8.4. The cascading effect of positioning the couch
This update causes two tokens to be sent through the network. One is a delete token for tv-2 with [position-none], and the other is an add token for tv-2 with [position-wall/south]. The delete causes the removal of the token from the right memory of node#2. The add would not match any patterns in this segment of the network.
The Rete network provides a number of performance improvements over a simple matching of rules to working memory:
• The root nodes act as indices into the network. Only those nodes which are affected by an update to working memory are processed.
• The patterns which have been successfully matched are saved in the node left and right memories. They do not have to be reprocessed.
• When rules share common sequences of patterns, that information is stored only once in the network, meaning it only has to be processed once.
• The output of the network is full rule instantiations. Once an instantiation is removed from the conflict set (due to a rule firing) it will not reappear on the conflict set, thus preventing multiple firings of the rule.
Next, let's look at the code to build a Rete pattern matcher. First we will look at the data structures used to define the Rete network, then the pattern matcher which propagates tokens through the network, and finally the rule compiler which builds the network from the rules.
The roots of the network are based on the frame patterns from the rules. The root nodes are represented as:
root(NID, Pattern, NextList).
NID is a generated identification for the node, Pattern is the frame pattern, and NextList is the list of succesor nodes which use the Pattern. NextList serves as the pointers connecting the network together.
For example:
root(2, wall-W with [opposite-OW], [1-r]).
The two-input nodes of the network have terms representing the patterns which are matched from the left and right inputs to the node. Together they form the template which determines if particular tokens will be successfully combined into rule instantiations. The format of this structure is:
bi(NID, LeftPattern, RightPattern, NextList).
Figure 8.5 Major predicates which propagate a token through the network
NID again is an identification. LeftPattern is the list of frame patterns that have been matched in nodes previous to this one. RightPattern is the new frame pattern which will be appended to the LeftPattern. NextList contains a list of successor nodes.
For example:
bi(1, [couch-C
with [position-wall/W]],
[wall-W with [opposite-OW],
[2-l, 3-l]).
bi(2, [couch-C
with [position-wall/W],
wall-W with [opposite-OW]],
[tv-TV with [position-none, place_on-floor]],
[rule(f3)]).
The end of the network is rules. The rules are stored as:
rul(N, LHS, RHS).
N is the identification of the rule. LHS is the list of frame patterns which represent the full left hand side of the rule. RHS is the actions to be taken when the rule is instantiated.
Tokens are generated from the updates to frame instances. There are only two update predicates for the network, addrete which adds tokens, and delrete which deletes them. Both take as input the Class, Name, and TimeStamp of the frame instance. Both are called from the Foops predicates which update working memory: assert_ws, retract_ws, and update_ws. The major predicates of addrete are shown in figure 8.5.
The
addrete predicate uses a simple repeat - fail loop to match the frame
instance against each of the root nodes. It looks like:
addrete(Class,
Name, TimeStamp) :-
root(ID, Class-Name with ReqList, NextList),
ffsend(Class, Name, ReqList, TimeStamp, NextList),
fail.
addrete(_, _, _).
The ffsend predicate fullfills the request pattern in the root by a call to the frame system predicate, getf. This fills in the values for the pattern thus creating a token. Next, send is called with an add token.
ffsend(Class,
Name, ReqList, TimeStamp, NextList) :-
getf(Class, Name, ReqList),
send(tok(add, [(Class-Name with ReqList)/TimeStamp]), NextList),
!.
The delrete predicate is analagous, the only difference being it sends a delete token through the network.
delrete(Class,
Name, TimeStamp) :-
root(ID, Class-Name with ReqList, NextList),
delr(Class, Name, ReqList, TimeStamp),
fail.
delrete(_, _, _).
delr(Class,
Name, ReqList, TimeStamp) :-
getf(Class, Name, ReqList),
!, send(tok(del, [(Class-Name with ReqList)/TimeStamp]), NextList).
delr(Class, Name, ReqList, TimeStamp).
Predicate send passes the token to each of the successor nodes in the list:
send(_, []).
send(Token,
[Node|Rest]) :-
sen(Node, Token),
send(Token, Rest).
The real work is done by sen. It has to recognize three cases:
• The token is being sent to a rule. In this case, the rule must be added to or deleted from the conflict set.
• The token is being sent to the left side of a two-input node. In this case, the token is added to or deleted from the left memory of the node. The list is then matched against the right memory elements to see if a larger token can be built and passed through the network.
• The token is being sent to the right side of a node. In this case, the token is added to or deleted from the right memory of the node. It is then compared against the left memory elements to see if a larger token can be built and passed through the network.

Note how Prolog's unification automatically takes care of variable bindings between the patterns in the node memory, and the instance in the token. In sen, the instance in Token is unified with one of the right or left patterns in bi, automatically causing the opposite pattern to become instantiated as well (or else the call to bi fails and the next bi is tried). This instantiated Right or Left is then sent to matchRight or matchLeft respectively.
Both matchRight and matchLeft take the instantiated Right or Left and compare it with the tokens stored in the right or left working memory associated with that node. If unification is successful, a new token is built by appending the right or left from the memory with the original token. The new token is then passed further with another call to send.
matchRight(Node,
AD, Token, Right, NextList) :-
memory(Node-r, Right),
append(Token, Right, NewTok),
send(tok(AD, NewTok), NextList),
fail.
matchRight(_,
_, _, _, _).
matchLeft(Node,
AD, Token, Left, NextList) :-
memory(Node-l, Left),
append(Left, Token, NewTok),
send(tok(AD, NewTok), NextList),
fail.
matchLeft(_, _, _, _, _).
Another type of node which is useful for the system handles the cases where the condition on the LHS of the rule is a test such as L > R, or member(X, Y), rather than a pattern to be matched against working memory. The test nodes just perform the test and pass the tokens through if they succeed. There is no memory associated with them.
A final node to make the system more useful is one to handle negated patterns in rules. It works as a normal node, keeping instances in its memory which match the pattern in the rule, however it only passes on tokens which do not match.
The rule compiler builds the Rete network from the rules. The compiler predicates are not as straight forward as the predicates which propagate tokens through the network. This is one of the rare cases where the power of Prolog's pattern matching actually gets in the way, and code needs to be written to overcome it.
The very unification which makes the pattern matching propagation predicates easy to code gets in the way of the rule compiler. We allow variables in the rules, which behave as normal Prolog variables, but when the network is built, we need to know which rules are matching variables and which are matching atoms. For example, one rule might have the pattern wall/W and another might have wall/east. These should generate two different indices when building the network, but Prolog would not distinguish between them since they unify with each other.
In order to distinguish between the variables and atoms in the frame patterns, we must pick the pattern apart first, binding the variables to special atoms as we go. Once all of the variables have been instantiated in this fashion, the patterns can be compared.
But first, let's look at the bigger picture. Each rule is compared, frame pattern by frame pattern, against the network which has been developed from the rules previously processed. The frame patterns of the rule are sent through the network in a similar fashion to the propagation of tokens. If the frame patterns in the rule are accounted for in the network, nothing is done. If a pattern is not in the network, then the network is updated to include it.
The
top level predicate for compiling rules into a Rete net, reads each rule and
compiles it. The major predicates involved in compiling rules into a Rete network
are shown in figure 8.6.
rete_compil
:-
rule N# LHS ==> RHS,
rete_comp(N, LHS, RHS),
fail.
rete_compil.
Figure 8.6 The major predicates for compiling rules into a Rete network
The next predicate, rete_comp, looks at the first frame pattern in the rule and determines if it should build a new root node or if one already exists. It then passes the information from the root node and the rest of the rule left hand side to retcom which continues traversing and/or building the network.
rete_comp(N,
[H|T], RHS) :-
term(H, Hw),
check_root(RN, Hw, HList),
retcom(root(RN), [Hw/_], HList, T, N, RHS),
!.
rete_comp(N, _, _) .
The term predicate merely checks for shorthand terms of the form Class-Name and replaces them with the full form Class-Name with []. Terms already in full form are left unchanged.
term(Class-Name, Class-Name with []).
term(Class-Name with List, Class-Name with List).
The check_root predicate determines if there is already a root node for the term, and if not creates one. It will be described in detail a little later. The third argument from check_root is the current list of nodes linked to this root.
The last goal is to call retcom, which is the main recursive predicate of the compilation process. It has six arguments, as follows:
PNID the id of the previous node
OutPat pattern from previous node
PrevList successor list from previous node
[H|T] list of remaining frame patterns in rule
N rule ID, for building the rule at the end
RHS RHS of the rule, for building the rule at the end
There are two cases recognized by retcom:
• All of the frame patterns in the rule have been compiled into the network, and all that is left is to link the full form of the rule to the network.
• The rule frame patterns processed so far match an existing two-input node, or a new one is created.
In Prolog, the first case is recognized by having the empty list as the list of remaining frame patterns. The rule is built, and update_node is called to link the previous node to the rule.
retcom(PNID,
OutPat, PrevList, [], N, RHS) :-
build_rule(OutPat, PrevList, N, RHS),
update_node(PNID, PrevList, rule-N),
!.
In the second case, the frame pattern being worked on (H) is first checked to see if it has a root node. Then the network is checked to see if a two-input node exists whose left input pattern matches the rule patterns processed so far (PrevNode). Either node might have been found or added, and then linked to the rest of the network.
retcom(PNID,
PrevNode, PrevList, [H|T], N, RHS) :-
term(H, Hw),
check_root(RN, Hw, HList),
check_node(PrevNode, PrevList, [Hw/_], HList, NID, OutPat, NList),
update_node(PNID, PrevList, NID-l),
update_root(RN, HList, NID-r),
!,
retcom(NID, OutPat, NList, T, N, RHS).
Building rules is simply accomplished by writing a new rule structure:
build_rule(OutPat,
PrevList, N, RHS) :-
assertz( rul(N, OutPat, RHS) ).
The check_root predicate is the first one that must deal with the pattern matching problem mentioned earlier. It covers three cases:
• There is no existing root which matches the term using Prolog's pattern matching. In this case a new root is added.
• There is an existing root which matches the term, atom for atom, variable for variable. In this case no new root is needed.
• There is no precise match and a new root is created.
In Prolog:
check_root(NID,
Pattern, []) :-
not(root(_, Pattern, _)),
gen_nid(NID),
assertz( root(NID, Pattern, []) ), !.
check_root(N,
Pattern, List) :-
asserta(temp(Pattern)),
retract(temp(T1)),
root(N, Pattern, List),
root(N, T2, _),
comp_devar(T1, T2), !.
check_root(NID,
Pattern, []) :-
gen_nid(NID),
assertz( root(NID, Pattern, []) ).
The first clause is straight forward. The gen_nid predicate is used to generate unique numbers for identifying nodes in the Rete network.
The second clause is the difficult one. The first problem is to make a copy of Pattern which Prolog will not unify with the original term. The easiest way is to assert the term and then retract it using a different variable name, as the first two goals of the second clause do. We now have both Pattern and T1 as identical terms, but Prolog doesn't know they are the same and will not bind the variables in one when they are bound in the other.
We can now use Pattern to find the root which matches it, using Prolog's match. Again, not wishing to unify the variables, we call the root again using just the root identification. This gives us T2, the exact pattern in the root before unification with Pattern.
Now we have T1 and T2, two terms which we know will unify in Prolog. The problem is to see if they are also identical in their placement of variables. For this we call comp_devar which compares two terms after unifying all of the variables with generated strings.
A very similar procedure is used for check_node. It is a little more complex in that it needs to build and return the tokens that are the two inputs to a node. The arguments to check_node are:
PNode token list from previous node
PList list of successor nodes from previous node
H new token being added
HList successor nodes from root for token H
NID returned ID of the node
OutPat returned tokenlist from the node
NList returned list of successor nodes from the node
The clauses for check_node are:
check_node(PNode,
PList, H, HList, NID, OutPat, []) :-
not (bi(_, PNode, H, _)),
append(PNode, H, OutPat),
gen_nid(NID),
assertz( bi(NID, PNode, H, []) ),
!.
check_node(PNode,
PList, H, HList, NID, OutPat, NList) :-
append(PNode, H, OutPat),
asserta(temp(OutPat)),
retract(temp(Tot1)),
bi(NID, PNode, H, NList),
bi(NID, T2, T3, _),
append(T2, T3, Tot2),
comp_devar(Tot1, Tot2),
check_node(PNode,
PList, H, HList, NID, OutPat, []) :-
append(PNode, H, OutPat),
gen_nid(NID),
assertz( bi(NID, PNode, H, []) ).
The update predicates check to see if the new node is on the list of links from the old node. If so, nothing is done. Otherwise a new link is added by putting the new node id on the list.
update_root(RN,
HList, NID) :-
member(NID, HList), !.
update_root(RN,
HList, NID) :-
retract( root(RN, H, HList) ),
asserta( root(RN, H, [NID|HList]) ).
update_node(root(RN),
HList, NID) :-
update_root(RN, HList, NID), !.
update_node(X,
PrevList, NID) :-
member(NID, PrevList), !.
update_node(PNID,
PrevList, NID) :-
retract( bi(PNID, L, R, _) ),
asserta( bi(PNID, L, R, [NID|PrevList]) ).
The comp_devar predicate takes each term it is comparing, and binds all the variables to generated terms.
comp_devar(T1,
T2) :-
del_variables(T1),
del_variables(T2),
T1=T2.
The del_variables predicate is used to bind the variables. The function which generates atoms to replace the variables is initialized the same way each time it is called, so if T1 and T2 have the same pattern of variables, they will be replaced with the same generated atoms and the terms will be identical.
del_variables(T)
:-
init_vargen,
de_vari(T).
The basic strategy is to recognize the various types of structures and break them into smaller components. When a component is identified as a variable, it is unified with a generated atom.
First, de_vari looks at the case where the terms are lists. This is used for comparing token lists in check_node. It is a standard recursive predicate which removes the variables from the head of the list, and recursively calls itself with the tail. Note that unification will cause all occurances of a variable in the head of the list to be bound to the same generated atom. The third clause covers the case where the term was not a list.
de_vari([]).
de_vari([H|T])
:-
de_var(H),
de_vari(T).
de_vari(X) :- de_var(X).
The first clause of de_var removes the time stamps from consideration. The next two clauses recognize the full frame pattern structure, and the attribute-value pair structure respectively.
de_var(X/_) :- de_var(X).
de_var(X-Y
with List) :-
de_v(X-Y),
de_vl(List), !.
de_var(X-Y)
:-
de_v(X-Y), !.
The next predicates continue to break the structures apart until finally d_v is given an elementary term as an argument. If the term is a variable, an atom is generated to replace it. Otherwise the term is left alone. Due to Prolog's unification, once one instance of a variable is unified to a generated term, all other instances of that variable are automatically unified to the same generated term. Thus, the generated atoms follow the same pattern as the variables in the full term.
de_vl([]).
de_vl([H|T])
:-
de_v(H),
de_vl(T).
de_v(X-Y)
:-
d_v(X),
d_v(Y).
d_v(V) :-
var(V),
var_gen(V), !.
d_v(_).
The next two predicates are used to generate the variable replacements. They are of the form '#VAR_N', where N is a generated integer. In this case two built-in predicates of AAIS Prolog are used to convert the integer to a string and concatenate it to the rest of the form of the variable. The same effect could be achieved with the standard built-in, name, and a list of ASCII characters representing the string.
init_vargen
:-
abolish(varg, 1),
asserta(varg(1)).
var_gen(V)
:-
retract(varg(N)),
NN is N+1,
asserta(varg(NN)),
int2string(N, NS),
stringconcat("#VAR_", NS, X),
name(V, X).
The system only handles simple rules so far, and does not take into account either negations or terms which are tests, such as comparing variables or other Prolog predicate calls.
Nodes to cover tests are easily added. They are very similar to the normal two-input nodes, but do not have memory associated with them. The left side is a token list just as in the two-input nodes. The right side has the test pattern. If a token passes the test, a new token with the test added is passed through the network.
The negated patterns store a count with each pattern in the left memory. That count reflects the number of right memory terms which match the left memory term. Only when the count is zero, is a token allowed to pass through the node.
Only a few changes have to be to Foops to incorporate the Rete network developed here.
A compile command is added to the main menu that builds the Rete network. It is called after the load command.
The commands to update working memory are modified to propagate tokens through the Rete network. This means calls to addrete and delrete as appropriate.
The refraction logic, which ensured the same instantiation would not be fired twice, is removed since it is no longer necessary.
The predicate which builds the conflict set is removed since the conflict set is maintained by the predicates which process the network. The predicates which sort the conflict set are still used to select a rule to fire.
There are a number of design tradeoffs made in this version. The first is the classic space versus speed tradeoff. At each Rete memory, a full copy of each token is saved. This allows it to be retrieved and matched quickly during execution. Much space could be saved by only storing pointers to the working memory elements. These would have to be retrieved and the token reconstructed when needed.
The other tradeoff is with the flexibility of the frame system. With the frames in the original Foops, the frame patterns in the rules could take advantage of inheritance and general classes as in the rules which determined a need for electrical plugs in a room. Since Rete-Foops instantiates the patterns before propagating tokens through the network, this does not work. This feature could be incorporated but would add to the burden and complexity of maintaining the network.
8.1 - Implement nodes which support rules which have tests such as X > Y, and negated frame patterns.
8.2 - The implementation described in this chapter makes heavy use of memory by storing the full tokens in left and right memories. Build a new system in which space is saved by storing a single copy of the token and having pointers to it in left and right memory. The stored tokens just match single frame patterns. The complex tokens in the middle of the network contain lists of pointers to the simple tokens.
8.3 - Experiment with various size systems to see the performance gains of the Rete version of Foops.
8.4 - Figure out a way to allow Rete-Foops to use inheritance in frame patterns. That is, fix it so the rule which finds electric plugs works.
8.5 - Build an indexed version of Clam and make performance experiments with it.
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Enthusiasm, growth, adaptability, and flexibility have been the drivers behind the success in my career.
When I was 9 years old I walked downstairs to our basement where my brother was flipping through a book about 5” thick titled HTML. I thought it was awesome that you could create something from nothing and make it look cool on the monitor in front of you. I made some basic “apps” with some headers and some paragraphs - that was the extent and my introduction to coding. In college I started some Code Academy courses, but was full-throttle engaged in my English degree, so those fell by the wayside.
The real motivator that got me seriously interested in coding again was a warm fall day in Cedar Hills, Utah. I was at a client’s house spraying down a giant gardening-bed retaining wall scrubbing down the year-old cured concrete trying to remove the streaks that had layered to the surface. My brain hurt. There was a lack of engagement for it. I’ve spent most of my life engaged in stimulating activities that challenged my brain and body - I need that...a challenge. WIthout a challenge, I tend to get restless.
Enter web development as a serious consideration for my next career. It had everything I needed: problem solving, creativity, complex interactions, and never-ending growth. Critical analysis boosted my syntax-debugging skills. My ability to adapt to new industries and new job requirements increased my ability to learn and integrate into coding faster. Playing a college sport taught me how to work with and contribute effectively to a team. Working with a high-producing sales agent taught me efficiency and thoroughness.
I look forward to the many new and exciting challenges and opportunities software development has to offer me.
Check Out My ProjectsA non-profit group which consults with long-term care facilities. They required a landing page to disseminate informational and educational materials. The Director and the Operations Manager wanted a site that was clean, modern, and mobile-responsive. They also wanted a form to capture user information as well as a payment function to receive charitable donations.
Built with React, Redux, Node, Postgresql, and Massive. Functionality imitates that of an e-commerce site, with the added benefit of being able to add your tasks, or "products". As you add your tasks they are automatically populated on the main screen with the option of deleting that task or adding it a "cart." The "Buy Task" most recent items are populated in the cart view, which you see when you click the cart route on the top right.
Built with React, Redux, Node, Postgresql, and Massive. Allows the user to log-in using Auth-0 which enables them to save their information on the user object. They can input companies they are interested in, add contacts which include a time-stamp for the latest action taken with that contact, and add notes related to that contact. Users can search through their companies, view their goals and job-related web-sites, and scroll through a resource drop-down menu that allows you to look at scores of job search resources.
How can I help? Give me a call or send me an email and I'll get back to you as soon as possible!
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About me
Full-stack web developer with complimentary front end experience supporting a bilingual clientele base. Earned a University of Washington certificate in Web Development with training in HTML, CSS, Javascript, as well as graphic design. Supported several small businesses with branding and establishing an impactful web presence. Possess a rock-solid work ethic, an ability to work in both team and individual settings, and a deep commitment to personal excellence. An advocate for diverse perspectives and overcoming barriers balanced with personal drive and integrity. I am passionate about joining a team that leverages my skills and fosters an environment of growth, hard work, and high standards.


Can you think of an analogy to describe HTML, CSS and the DOM? How would you describe it to your non-technical friend?
I think of a website as a structure built from many components: If you think about it as as house, you can break it down. First you start with the bones of the house- the html, the foundations and structures of the building. When its time to look at the the interior, thats where we bring in CSS. Think of the CSS as the carpet, curtains, paint, colors, furniture etc. Javascript is the functions in which you interact with the house. Ie. how you open doors, the garage door opener etc. The DOM s then architectural plans for the house, it will tell you how each component works, where it is and what you can add to it if you wish to make any renovations in future.
What is meant by boxifying design?
Boxifying Design is a concept that comes from the fact that everything on the internet is in boxes, well every element that we see, no matter what shape it is, is actually a box. Everything breaks down to an html element, and every html element is square. Boxifying design is a method many front end developers use when given a design from a designer, they will then go through the page and “boxify” it by drawing boxes around it to break down the components into elements.
What is the box model?
As all html elements are actually boxes- The box model is the box that is made around each html element, shown in CSS as a box within a box, within a box etc- It includes the margin, border, padding and content.


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How many internal nodes does this tree have?
ANS
Anything that is not a leaf node is an internal node. Internal nodes might have 1 or 2 children.
How many leaf nodes does this tree have?
ANS
Anything that has no children is a leaf node.
How many nodes in the tree have at least one sibling?
ANS
Siblings must have the same parent. If a node has two children, then each such child has a sibling.
How many descendents does the root of this tree have?
ANS
Every node except the root is a descendent.
What is the height of this tree?
Count the number of steps to the deepest node, and add 1.
What is the depth of this tree?
Nodes have depth.
Which statement is correct?
Do any internal nodes have only one child? If so, the tree is not full.
A complete tree fills in nodes level by level, with the bottom level filled in from left to right.