HDFS Snapshots are read-only point-in-time copies of the file system. Snapshots can be taken on a subtree of the file system or the entire file system. Some common use cases of snapshots are data backup, protection against user errors and disaster recovery.
The implementation of HDFS Snapshots is efficient:
Snapshot creation is instantaneous: the cost is O(1) excluding the inode lookup time.
Additional memory is used only when modifications are made relative to a snapshot: memory usage is O(M), where M is the number of modified files/directories.
Blocks in datanodes are not copied: the snapshot files record the block list and the file size. There is no data copying.
Snapshots do not adversely affect regular HDFS operations: modifications are recorded in reverse chronological order so that the current data can be accessed directly. The snapshot data is computed by subtracting the modifications from the current data.
Snapshots can be taken on any directory once the directory has been set as snapshottable. A snapshottable directory is able to accommodate 65,536 simultaneous snapshots. There is no limit on the number of snapshottable directories. Administrators may set any directory to be snapshottable. If there are snapshots in a snapshottable directory, the directory can be neither deleted nor renamed before all the snapshots are deleted.
Nested snapshottable directories are currently not allowed. In other words, a directory cannot be set to snapshottable if one of its ancestors/descendants is a snapshottable directory.
For a snapshottable directory, the path component “.snapshot” is used for accessing its snapshots. Suppose /foo is a snapshottable directory, /foo/bar is a file/directory in /foo, and /foo has a snapshot s0. Then, the path /foo/.snapshot/s0/bar refers to the snapshot copy of /foo/bar. The usual API and CLI can work with the “.snapshot” paths. The following are some examples.
Listing all the snapshots under a snapshottable directory:
hdfs dfs -ls /foo/.snapshot
Listing the files in snapshot s0:
hdfs dfs -ls /foo/.snapshot/s0
Copying a file from snapshot s0:
hdfs dfs -cp -ptopax /foo/.snapshot/s0/bar /tmp
Note that this example uses the preserve option to preserve timestamps, ownership, permission, ACLs and XAttrs.
The HDFS snapshot feature introduces a new reserved path name used to interact with snapshots: .snapshot. When upgrading from an older version of HDFS which does not support snapshots, existing paths named .snapshot need to first be renamed or deleted to avoid conflicting with the reserved path. See the upgrade section in the HDFS user guide for more information.
The operations described in this section require superuser privilege.
Allowing snapshots of a directory to be created. If the operation completes successfully, the directory becomes snapshottable.
Command:
hdfs dfsadmin -allowSnapshot <path>
Arguments:
| path | The path of the snapshottable directory. |
See also the corresponding Java API void allowSnapshot(Path path) in HdfsAdmin.
Disallowing snapshots of a directory to be created. All snapshots of the directory must be deleted before disallowing snapshots.
Command:
hdfs dfsadmin -disallowSnapshot <path>
Arguments:
| path | The path of the snapshottable directory. |
See also the corresponding Java API void disallowSnapshot(Path path) in HdfsAdmin.
The section describes user operations. Note that HDFS superuser can perform all the operations without satisfying the permission requirement in the individual operations.
Create a snapshot of a snapshottable directory. This operation requires owner privilege of the snapshottable directory.
Command:
hdfs dfs -createSnapshot <path> [<snapshotName>]
Arguments:
| path | The path of the snapshottable directory. |
| snapshotName | The snapshot name, which is an optional argument. When it is omitted, a default name is generated using a timestamp with the format "'s'yyyyMMdd-HHmmss.SSS", e.g. "s20130412-151029.033". |
See also the corresponding Java API Path createSnapshot(Path path) and Path createSnapshot(Path path, String snapshotName) in FileSystem The snapshot path is returned in these methods.
Delete a snapshot of from a snapshottable directory. This operation requires owner privilege of the snapshottable directory.
Command:
hdfs dfs -deleteSnapshot <path> <snapshotName>
Arguments:
| path | The path of the snapshottable directory. |
| snapshotName | The snapshot name. |
See also the corresponding Java API void deleteSnapshot(Path path, String snapshotName) in FileSystem.
Rename a snapshot. This operation requires owner privilege of the snapshottable directory.
Command:
hdfs dfs -renameSnapshot <path> <oldName> <newName>
Arguments:
| path | The path of the snapshottable directory. |
| oldName | The old snapshot name. |
| newName | The new snapshot name. |
See also the corresponding Java API void renameSnapshot(Path path, String oldName, String newName) in FileSystem.
Get all the snapshottable directories where the current user has permission to take snapshtos.
Command:
hdfs lsSnapshottableDir
Arguments: none
See also the corresponding Java API SnapshottableDirectoryStatus[] getSnapshottableDirectoryListing() in DistributedFileSystem.
Get the differences between two snapshots. This operation requires read access privilege for all files/directories in both snapshots.
Command:
hdfs snapshotDiff <path> <fromSnapshot> <toSnapshot>
Arguments:
| path | The path of the snapshottable directory. |
| fromSnapshot | The name of the starting snapshot. |
| toSnapshot | The name of the ending snapshot. |
Note that snapshotDiff can be used to get the difference report between two snapshots, or between a snapshot and the current status of a directory. Users can use “.” to represent the current status.
Results:
| + | The file/directory has been created. |
| - | The file/directory has been deleted. |
| M | The file/directory has been modified. |
| R | The file/directory has been renamed. |
A RENAME entry indicates a file/directory has been renamed but is still under the same snapshottable directory. A file/directory is reported as deleted if it was renamed to outside of the snapshottble directory. A file/directory renamed from outside of the snapshottble directory is reported as newly created.
The snapshot difference report does not guarantee the same operation sequence. For example, if we rename the directory “/foo” to “/foo2”, and then append new data to the file “/foo2/bar”, the difference report will be:
R. /foo -> /foo2 M. /foo/bar
I.e., the changes on the files/directories under a renamed directory is reported using the original path before the rename (“/foo/bar” in the above example).
See also the corresponding Java API SnapshotDiffReport getSnapshotDiffReport(Path path, String fromSnapshot, String toSnapshot) in DistributedFileSystem.


Add a new trip
My trip to:
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My trip to:
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BITSystemProfile Class Reference
| Inherits from | NSObject |
| Declared in | BITSystemProfile.h |
Tasks
Initialization
Generic
-
+ deviceIdentifier
-
+ deviceModel
-
+ systemVersionString
-
– systemDataForBundle:
-
– systemData
-
– systemUsageDataForBundle:
-
– systemUsageData
Usage time
Class Methods
deviceIdentifier
Return the current devices identifier
+ (NSString *)deviceIdentifier
Return Value
NSString with the device identifier
Declared In
BITSystemProfile.h
deviceModel
Return the current device model
+ (NSString *)deviceModel
Return Value
NSString with the repesentation of the device model
Declared In
BITSystemProfile.h
Instance Methods
startUsage
Start recording usage time for the current app
- (void)startUsage
Declared In
BITSystemProfile.h
startUsageForBundle:
Start recording usage time for a specific app or framework bundle
- (void)startUsageForBundle:(NSBundle *)bundle
Parameters
- bundle
The app or framework bundle to measure the usage time for
Declared In
BITSystemProfile.h
systemData
Return an array with system data
- (NSMutableArray *)systemData
Return Value
NSMutableArray with system data
Declared In
BITSystemProfile.h
systemDataForBundle:
Return an array with system data for a specific bundle
- (NSMutableArray *)systemDataForBundle:(NSBundle *)bundle
Parameters
- bundle
The app or framework bundle to get the system data from
Return Value
NSMutableArrray with system data
Declared In
BITSystemProfile.h
systemUsageData
Return an array with system usage data that can be used with Sparkle
- (NSMutableArray *)systemUsageData
Return Value
NSMutableArray with system and app usage data
Discussion
Call this method in the Sparkle delegate feedParametersForUpdater:sendingSystemProfile:
to attach system and app data to each Sparkle request
Declared In
BITSystemProfile.h
systemUsageDataForBundle:
Return an array with system usage data for a specific bundle
- (NSMutableArray *)systemUsageDataForBundle:(NSBundle *)bundle
Parameters
- bundle
The app or framework bundle to get the usage data from
Return Value
NSMutableArray with system and bundle usage data
Declared In
BITSystemProfile.h


Given two observables NestedArray$
and ReductionOperator$
, create a new observable Calculated$
that applies the reduction operator to a flattened version of NestedArray$
.
NestedArray$
will either be an integer or another
NestedArray$
. There are no limits to the depth of the array.ReductionOperator$
should emit either "Add" or
"Multiply".Calculated$
should be set to the sum of
all of the elements of the flattened array. When "Multiply" is emitted, Calculated$
should be set to the product of all of the elements of the flattened
array.[2, 3, 4, [5, [6, 7, 8], 9]]
and
"Add"
the output
should be calculated by the operation 2+3+4+5+6+7+8+9 leading to the solution of 54
.Please provide relevant tests to accompany your product.
Note: A new solution should be calculated/emitted whenever either input stream is altered. If an input is changed while the task is still calculating, the result from the first task should emit before the second.
The below buttons may assist your development and debugging.
Emitted (and Flattened) Array: {{ NestedArray$ | async }}
Current Operator: {{ ReductionOperator$ | async }}


Cologne bring in Markus Gisdol as part of reshuffle
by FSA EditorMarkus Gisdol has been confirmed as the new head coach of lowly Cologne, while Horst Heldt takes over as sporting director
Bundesliga strugglers Cologne have announced Markus Gisdol as their new head coach, while Horst Heldt has been appointed sporting director.
Gisdol has signed a contract that runs until June 2021 and replaces the recently sacked Achim Beierlorzer, who returned to work on Monday with German top-flight rivals Mainz.
Beierlorzer lost his final four games at the helm to leave Cologne 17th and at risk of relegation from the top tier.
Gisdol will be joined by a new sporting director in Heldt, who has also penned a one-and-a-half-year deal, in the hope major changes can lead to an upturn in fortunes.
Former Hoffenheim and Hamburg boss Gisdol told the club’s official website: “Cologne is a top club in German football.
“The current situation is not easy, but I know these challenges and I am totally convinced that we can overcome these. I want to help the team as quickly as possible, to come back to their undoubted potential.”
Cologne return to action after the international break with a trip to second-place RB Leipzig at the weekend.


Class TouchInfo
Copy of the UnityEngine.Touch structure, usable for network messages.
Inheritance
System.Object
TouchInfo
Assembly: Assembly-CSharp.dll
Syntax
Fields
|
Improve this Doc
View Source
altitudeAngle
Declaration
public float altitudeAngle
Field Value
| Type |
Description |
| System.Single |
|
|
Improve this Doc
View Source
azimuthAngle
Declaration
public float azimuthAngle
Field Value
| Type |
Description |
| System.Single |
|
|
Improve this Doc
View Source
deltaPosition
Declaration
public Vector2 deltaPosition
Field Value
| Type |
Description |
| UnityEngine.Vector2 |
|
|
Improve this Doc
View Source
deltaTime
Declaration
Field Value
| Type |
Description |
| System.Single |
|
|
Improve this Doc
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fingerId
Declaration
Field Value
| Type |
Description |
| System.Int32 |
|
|
Improve this Doc
View Source
maximumPossiblePressure
Declaration
public float maximumPossiblePressure
Field Value
| Type |
Description |
| System.Single |
|
|
Improve this Doc
View Source
phase
Declaration
Field Value
| Type |
Description |
| UnityEngine.TouchPhase |
|
|
Improve this Doc
View Source
position
Declaration
Field Value
| Type |
Description |
| UnityEngine.Vector2 |
|
|
Improve this Doc
View Source
pressure
Declaration
Field Value
| Type |
Description |
| System.Single |
|
|
Improve this Doc
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radius
Declaration
Field Value
| Type |
Description |
| System.Single |
|
|
Improve this Doc
View Source
radiusVariance
Declaration
public float radiusVariance
Field Value
| Type |
Description |
| System.Single |
|
|
Improve this Doc
View Source
rawPosition
Declaration
public Vector2 rawPosition
Field Value
| Type |
Description |
| UnityEngine.Vector2 |
|
|
Improve this Doc
View Source
tapCount
Declaration
Field Value
| Type |
Description |
| System.Int32 |
|
|
Improve this Doc
View Source
type
Declaration
Field Value
| Type |
Description |
| UnityEngine.TouchType |
|
Operators
|
Improve this Doc
View Source
Implicit(TouchInfo to Touch)
Returns a UnityEngine.Touch struct copied from a TouchInfo.
Declaration
public static implicit operator Touch(TouchInfo touchMessage)
Parameters
Returns
| Type |
Description |
| UnityEngine.Touch |
|
|
Improve this Doc
View Source
Implicit(Touch to TouchInfo)
Returns a TouchInfo copied from a UnityEngine.Touch struct.
Declaration
public static implicit operator TouchInfo(Touch touch)
Parameters
| Type |
Name |
Description |
| UnityEngine.Touch |
touch |
|
Returns


Summarise results from simulation studies and compute Monte Carlo standard errors of commonly used summary statistics. This package is modelled on the 'simsum' user-written command in 'Stata' (See White I.R., 2010 <http://www.stata-journal.com/article.html?article=st0200>).
| Version: | 0.3.3 |
| Depends: | R (≥ 2.10) |
| Imports: | checkmate, ggplot2, stats |
| Suggests: | covr, devtools, dplyr, eha, knitr, rmarkdown, rstpm2, survival, testthat |
| Published: | 2018-06-20 |
| Author: | Alessandro Gasparini [aut, cre], Ian R. White [aut] |
| Maintainer: | Alessandro Gasparini <ag475 at leicester.ac.uk> |
| BugReports: | https://github.com/ellessenne/rsimsum/issues |
| License: | GPL (≥ 3) |
| URL: | https://github.com/ellessenne/rsimsum |
| NeedsCompilation: | no |
| Citation: | rsimsum citation info |
| CRAN checks: | rsimsum results |
| Reference manual: | rsimsum.pdf |
| Vignettes: |
Introduction to rsimsum Visualising results from rsimsum Simulating a simulation study rsimsum and the tidyverse |
| Package source: | rsimsum_0.3.3.tar.gz |
| Windows binaries: | r-devel: rsimsum_0.3.3.zip, r-release: rsimsum_0.3.3.zip, r-oldrel: rsimsum_0.3.3.zip |
| OS X binaries: | r-release: rsimsum_0.3.3.tgz, r-oldrel: rsimsum_0.3.3.tgz |
| Old sources: | rsimsum archive |
Please use the canonical form https://CRAN.R-project.org/package=rsimsum to link to this page.


| 1083 | (A) | Als Titus after one a tym abowte the Cete rydys |
| 1087 | (C) | ¶ As tytus on a tyme . a-bowte þe towne rode |
| 1070 | (D) | ¶ As tytus aftir on a tyme a-bout þe toun ridis |
| 1050 | (E) | AS tytus after on a tyme . abowte þe town rydetħ |
| 42 | (Ex) | . . .boute þe towne rydes |
| 1108 | (L) | As tytus after a tyme vmbe þe toun redeþ |
| 1022 | (P) | . . . |
| 1059 | (U) | As Titus on a tyme / about the towne rides |
| 148 | (V) | As Titus after on a tyme . abouten þe towne rides |


The Web UI Framework is a set of widgets and other components for jQuery Mobile.
To get started, view the full listing of entries.
This site provides API documentation for the widgets of the Web UI Framework.
The Web UI Framework supports jQuery Mobile 1.3.0 to 1.4.3, and jQuery 1.7.0 to 1.11.2.
To download the Web UI Framework, first download jQuery Mobile. Then, add the Web UI Framework JS and CSS to a Web page after you have already added jQuery Mobile. The Web UI Framework JS and CSS files can be found here:


Aloysius Pang’s family: Set up preventive measures for future sons
by David SunThe family of Aloysius Pang has urged that "preventive measures" be put in place to prevent another tragedy.
In an Instagram post on the late actor's management agency NoonTalk Media on Tuesday, Mr Jefferson Pang, his older brother, said the family believes one loss is enough.
He said: "Other parents' sons have a life ahead of them. It is not about blame and pointing fingers now but how it should be prevented in the future.
"Complacency shouldn't be human error alone and preventive measures should be in place for future sons."
Corporal First Class (NS) Aloysius Pang, 28, an armament technician from the 268th Battalion Singapore Artillery, died on Jan 23, four days after he was seriously injured while in a Singapore Self-Propelled Howitzer (SSPH) during a military exercise in New Zealand.
A Committee of Inquiry that was convened after the incident found all three soldiers, including CFC Pang, who were in the SSPH to conduct repair works had committed safety lapses that eventually led to the death of the actor.
Following CFC Pang's death, additional measures such as bold markings to indicate the safe and potentially hazardous areas were put up in the SSPH.
All SSPH crew now also have to practise emergency stop button drills before operating the platform.
In addition, army technicians now have to go through a nine-step drill before their maintenance training and tasks so that any potential risks are reviewed, dry runs are conducted, and roles and responsibilities are clarified.
Military Expert 2 Ivan Teo Gee Siang, 35, and Third Sergeant (NS) Hubert Wah Yun Teng, 31, were fined $7,000 and $8,000 respectively by a military court on Tuesday. Wah was also demoted to the rank of corporal.
The court also heard that CFC Pang's family had reached out to the Singapore Armed Forces for leniency to be exercised in the sentencing of the two men. - DAVID SUN