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Add column with number of days between dates in DataFrame pandas
...f['B']
Out[12]:
one -58 days
two -26 days
dtype: timedelta64[ns]
In [13]: df['C'] = df['A'] - df['B']
In [14]: df
Out[14]:
A B C
one 2014-01-01 2014-02-28 -58 days
two 2014-02-03 2014-03-01 -26 days
Note: ensure you're using a new of pandas (e.g. 0.13.1), this ma...
Why are Perl 5's function prototypes bad?
...like this:
sub mypush(\@@) { ... }
and call it as
mypush @array, 1, 2, 3;
without needing to write the \ to take a reference to the array.
In a nutshell, prototypes let you create your own syntactic sugar. For example the Moose framework uses them to emulate a more typical OO syntax.
This is...
Converting string to numeric [duplicate]
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132
I suspect you are having a problem with factors. For example,
> x = factor(4:8)
> x
[1]...
What are the big improvements between guava and apache equivalent libraries?
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3 Answers
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What do the plus and minus signs mean in Objective-C next to a method?
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edited May 23 '17 at 12:18
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answered Jan 19 '10 at 21:39
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Difference between RegisterStartupScript and RegisterClientScriptBlock?
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163
Here's an old discussion thread where I listed the main differences and the conditions in which ...
How to get the size of a JavaScript object?
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edited May 23 '17 at 12:18
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answered Aug 10 '12 at 10:55
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What is the difference between user variables and system variables?
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132
Right-click My Computer and go to Properties->Advanced->Environmental Variables...
What'...
What's an elegant way to conditionally add a class to an HTML element in a view?
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143
I use the first way, but with a slightly more succinct syntax:
<div class="<%= 'ok' if @s...
SQL SELECT speed int vs varchar
...cupy between 2 and 8 bytes, with 4 being usually more than enough ( -2147483648 to +2147483647 )
character types occupy 4 bytes plus the actual strings.
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