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What is the purpose of a question mark after a type (for example: int? myVariable)?
...d the values true, false, or
null. The ability to assign null to numeric and Boolean types is
especially useful when you are dealing with databases and other data
types that contain elements that may not be assigned a value. For
example, a Boolean field in a database can store the values tru...
How to modify existing, unpushed commit messages?
...t commit. Additionally, you can set the commit message directly in the command line with:
git commit --amend -m "New commit message"
…however, this can make multi-line commit messages or small corrections more cumbersome to enter.
Make sure you don't have any working copy changes staged before do...
What is the purpose of fork()?
In many programs and man pages of Linux, I have seen code using fork() . Why do we need to use fork() and what is its purpose?
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How do I capture SIGINT in Python?
I'm working on a python script that starts several processes and database connections. Every now and then I want to kill the script with a Ctrl + C signal, and I'd like to do some cleanup.
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How to disable Golang unused import error
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If you add the underscore to "fmt" in Gogland, it automatically adds "fmt" so that you have both _"fmt" and "fmt", which renders it useless in this IDE
– kramer65
Sep 8 '17 at 8:54
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How to draw vertical lines on a given plot in matplotlib?
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The standard way to add vertical lines that will cover your entire plot window without you having to specify their actual height is plt.axvline
import matplotlib.pyplot as plt
plt.axvline(x=0.22058956)
plt.axvline(x=0.33088437)
p...
throws Exception in finally blocks
Is there an elegant way to handle exceptions that are thrown in finally block?
15 Answers
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How does one generate a random number in Apple's Swift language?
I realize the Swift book provided an implementation of a random number generator. Is the best practice to copy and paste this implementation in one's own program? Or is there a library that does this that we can use now?
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How to call shell commands from Ruby
How do I call shell commands from inside of a Ruby program? How do I then get output from these commands back into Ruby?
20...
Remove an entire column from a data.frame in R
...on't need drop argument cause it always return data.frame from data.frame. And I think this is much better way to localized columns (and only columns) in data.frame (and it's faster). Check: cars[-1] (one col data.frame) or better cars[-(1:2)]: data frame with 0 columns and 50 rows.
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