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Quit and restart a clean R session from within R?
Is there a way I can make an alias, within R, that will execute q() and then restart a clean R session?
12 Answers
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What is the difference between “ is None ” and “ ==None ”
...
The answer is explained here.
To quote:
A class is free to implement
comparison any way it chooses, and it
can choose to make comparison against
None mean something (which actually
makes sense; if someone told you to
implement the None object f...
How do I escape ampersands in batch files?
...example:
start http://www.google.com/search?client=opera^&rls=en^&q=escape+ampersand%20and%20percentage+in+cmd^&sourceid=opera^&ie=utf-8^&oe=utf-8
From a batch file
& is escaped like this: ^& (based on @Wael Dalloul's answer)
% is escaped like this: %% (based on the ...
Fetch frame count with ffmpeg
...4V/M4A/MOV can affect your frame number. See Edit lists below.
ffprobe: Query the container
ffprobe -v error -select_streams v:0 -show_entries stream=nb_frames -of default=nokey=1:noprint_wrappers=1 input.mp4
This is a fast method.
Not all formats (such as Matroska) will report the number of ...
Multiline strings in VB.NET
...rals to achieve a similar effect:
Imports System.XML
Imports System.XML.Linq
Imports System.Core
Dim s As String = <a>Hello
World</a>.Value
Remember that if you have special characters, you should use a CDATA block:
Dim s As String = <![CDATA[Hello
World & Space]]>.Value
20...
Launching Google Maps Directions via an intent on Android
...ntent(android.content.Intent.ACTION_VIEW,
Uri.parse("google.navigation:q=an+address+city"));
UPDATE
In May 2017 Google launched the new API for universal, cross-platform Google Maps URLs:
https://developers.google.com/maps/documentation/urls/guide
You can use Intents with the new API as wel...
Search for selection in vim
...
Answer
Yank the text you want to search for
q/p
Enter
Explanation
q/ works similarly to vanilla search / except you're in command mode so p actually does "paste" instead of typing the character p. So the above will copy the text you're searching for and paste it int...
How do I install cygwin components from the command line?
...ite themselves. Someone have to work on them. And since their usability is quite limited (to overwrite files currently in use on Windows you have to close Cygwin first, so it's not possible to execute any package manager in closed Cygwin :), there isn't many people interested.
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Check if directory mounted with bash
...s no need for the test, or the subshell created by $(). if command | grep -q 'stuff'; then ...
– jordanm
Feb 23 '12 at 23:54
32
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How to escape text for regular expression in Java
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Since Java 1.5, yes:
Pattern.quote("$5");
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