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C# convert int to string with padding zeros?
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i.ToString().PadLeft(4, '0') - okay, but doesn't work for negative numbers
i.ToString("0000"); - explicit form
i.ToString("D4"); - short form format specifier
$"{i:0000}"; - string interpolation (C# 6.0+)
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How does Go update third-party packages?
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tux21btux21b
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How to sort a dataframe by multiple column(s)
...f the example(order) code:
R> dd[with(dd, order(-z, b)), ]
b x y z
4 Low C 9 2
2 Med D 3 1
1 Hi A 8 1
3 Hi A 9 1
Edit some 2+ years later: It was just asked how to do this by column index. The answer is to simply pass the desired sorting column(s) to the order() function:
R> dd[orde...
Disable ActiveRecord for Rails 4
I want to disable ActiveRecord in Rails 4. I did the following in config/application.rb
8 Answers
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Generate random numbers uniformly over an entire range
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154
Why rand is a bad idea
Most of the answers you got here make use of the rand function and the mo...
Git alias with positional parameters
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edited Mar 4 '18 at 13:20
Eugen Konkov
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Is there any way to close a StreamWriter without closing its BaseStream?
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If you are using .NET Framework 4.5 or later, there is a StreamWriter overload using which you can ask the base stream to be left open when the writer is closed.
In earlier versions of .NET Framework prior to 4.5, StreamWriter assumes it owns the stream. ...
What is :: (double colon) in Python when subscripting sequences?
I know that I can use something like string[3:4] to get a substring in Python, but what does the 3 mean in somesequence[::3] ?
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mongo - couldn't connect to server 127.0.0.1:27017
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This error is what you would see if the mongo shell was not able to talk to the mongod server.
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How to check the extension of a filename in a bash script?
...of $file equal to .txt?" If so, you can use the following:
if [ ${file: -4} == ".txt" ]
Note that the space between file: and -4 is required, as the ':-' modifier means something different.
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