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How to get execution time in rails console?
... Jeremy Baker
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answered Aug 19 '10 at 13:35
ShadwellShadwell
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How to use Active Support core extensions
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How many double numbers are there between 0.0 and 1.0?
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Java doubles are in IEEE-754 format, therefore they have a 52-bit fraction; between any two adjacent powers of two (inclusive of one and exclusive of the next one), there will therefore be 2 to the 52th power different doubles (i.e., 4503599627370496 ...
How do I make a matrix from a list of vectors in R?
...is to use do.call():
> do.call(rbind, a)
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 1 1 2 3 4 5
[2,] 2 1 2 3 4 5
[3,] 3 1 2 3 4 5
[4,] 4 1 2 3 4 5
[5,] 5 1 2 3 4 5
[6,] 6 1 2 3 4 5
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How assignment works with Python list slice?
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NPENPE
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What does the caret operator (^) in Python do?
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cartesian product in pandas
...':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 1 3 5
1 1 3 6
2 2 4 5
3 2 4 6
See here for the documentation: http://pandas.pydata....
how to check redis instance version?
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answered Feb 4 '14 at 15:03
Aviram NetanelAviram Netanel
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RegEx - Match Numbers of Variable Length
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Splitting a list into N parts of approximately equal length
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65
This code is broken due to rounding errors. Do not use it!!!
assert len(chunkIt([1,2,3], 10)) =...