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How do I capture the output into a variable from an external process in PowerShell?
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JNKJNK
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How to pad zeroes to a string?
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2506
Strings:
>>> n = '4'
>>> print(n.zfill(3))
004
And for numbers:
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Multiple glibc libraries on a single host
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It is very possible to have multiple versions of glibc on the same system (we do that every da...
How do I merge a list of dicts into a single dict?
... d in L:
... result.update(d)
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>>> result
{'a':1,'c':1,'b':2,'d':2}
As a comprehension:
# Python >= 2.7
{k: v for d in L for k, v in d.items()}
# Python < 2.7
dict(pair for d in L for pair in d.items())
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Truncate number to two decimal places without rounding
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How do I delete rows in a data frame?
...he '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" myData if you wanted to drop those rows entirely---otherwise, R just prints the results.
myData <- myData[-c(2, 4, 6), ]
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Permission denied (publickey) when SSH Access to Amazon EC2 instance [closed]
I want to use my Amazon ec2 instance but faced the following error:
29 Answers
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How to set a Timer in Java?
How to set a Timer, say for 2 minutes, to try to connect to a Database then throw exception if there is any issue in connection?
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How to use the 'sweep' function
...ation defined by FUN.
For instance, if you want to add 1 to the 1st row, 2 to the 2nd, etc. of the matrix you defined, you will do:
sweep (M, 1, c(1: 4), "+")
I frankly did not understand the definition in the R documentation either, I just learned by looking up examples.
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Why is parenthesis in print voluntary in Python 2.7?
In Python 2.7 both the following will do the same
4 Answers
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