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Regex group capture in R with multiple capture-groups
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118
str_match(), from the stringr package, will do this. It returns a character matrix with one co...
How to validate IP address in Python? [duplicate]
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11 Answers
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Active
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Pass a data.frame column name to a function
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109
You can just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 &...
Behaviour of increment and decrement operators in Python
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1091
++ is not an operator. It is two + operators. The + operator is the identity operator, which ...
Is it safe to use -1 to set all bits to true?
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155
I recommend you to do it exactly as you have shown, since it is the most straight forward one....
Shortest distance between a point and a line segment
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Batch files - number of command line arguments
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105
Googling a bit gives you the following result from wikibooks:
set argC=0
for %%x in (%*) do S...
What do the numbers in a version typically represent (i.e. v1.9.0.1)?
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In version 1.9.0.1:
1: Major revision (new UI, lots of new features, conceptual change, etc.)
9: Minor revision (maybe a change to a search box, 1 feature added, collection of bug fixes)
0: Bug fix release
1: Build number (if used)—...
How do I iterate through each element in an n-dimensional matrix in MATLAB?
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You can use linear indexing to access each element.
for idx = 1:numel(array)
element = array(idx)
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end
This is useful if you don't need to know what i,j,k, you are at. However, if you don't need to know what index you are at, you are probably better off using arrayfun()
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