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How to reorder data.table columns (without copying)
... 2 2
# [3,] 0.3297416 1 3
From ?setcolorder:
In data.table parlance, all set* functions change their input by reference. That is, no copy is made at all, other than temporary working memory, which is as large as one column.
so should be pretty efficient. See ?setcolorder for details.
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how does array[100] = {0} set the entire array to 0?
...se an empty initializer list, causing the compiler to aggregate-initialize all of the elements of the array:
char array[100] = {};
As for what sort of code the compiler might generate when you do this, take a look at this question: Strange assembly from array 0-initialization
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GitHub: searching through older versions of files
I know that using GitHub I can search through all the current versions of my files in a repo. However, I would also like to search through the older versions of my repo files. For example, say, I used to have a function called get_info() in my code, but deleted it several versions ago, is it possibl...
Browsers' default CSS for HTML elements
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A GitHub repository of all W3C HTML spec and vendor default CSS stylesheets can be found here
1. Default Styles for Firefox
2. Default Styles for Internet Explorer
3. Default Styles for Chrome / Webkit
4. Default Styles for Opera
5. Default St...
'await' works, but calling task.Result hangs/deadlocks
...g to schedule its continuation onto a thread that is being blocked by the call to Result.
In this case, your SynchronizationContext is the one used by NUnit to execute async void test methods. I would try using async Task test methods instead.
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JavaScript/regex: Remove text between parentheses
...the parentheses are in the middle of a string, the regex above will remove all the whitespace around them. This is probably not good.
– Nigel Johnson
Nov 13 '17 at 11:42
1
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Build .so file from .c file using gcc command line
...lo.c
to do it in one step. – Jonathan Leffler
I also suggest to add -Wall to get all warnings, and -g to get debugging information, to your gcc commands. – Basile Starynkevitch
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impro...
Reuse Cucumber steps
...E: The method described below has been deprecated. The recommended way to call a step from within another step now looks like this:
Given /^I login successfully$/
step "I login with valid credentials"
end
Old, deprecated method (for reference):
You can call steps from other steps like th...
git push to specific branch
...I'm a bit confused, I'm using v2.10, when I type git push it tries to push all tracked branches, contrary to what you said ("the remote of the current branch is the default value").
– Roberto
Feb 22 '17 at 0:00
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What is the difference between related SQLite data-types like INT, INTEGER, SMALLINT and TINYINT?
When creating a table in SQLite3, I get confused when confronted with all the possible datatypes which imply similar contents, so could anyone tell me the difference between the following data-types?
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