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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
I am working with the pandas library and I want to add two new columns to a dataframe df with n columns (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
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Stripping out non-numeric characters in string
... fractions, subscripts, superscripts, Roman numerals, currency numerators, and encircled numbers. This method contrasts with the IsDigit method, which determines whether a Char is a radix-10 digit." msdn.microsoft.com/en-us/library/yk2b3t2y.aspx
– LukeH
Oct 20 ...
How to add months to a date in JavaScript? [duplicate]
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Split your date into year, month, and day components then use Date:
var d = new Date(year, month, day);
d.setMonth(d.getMonth() + 8);
Date will take care of fixing the year.
share
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MVVM: Tutorial from start to finish?
...e with no WPF experience up-to-speed enough so that (s)he can fully understand how the series’ demo application works.
Bea Stollnitz (link is to her archives) has a number of great articles on WPF.
WPF: A Beginner's Guide - Part 1 of n by Sacha Barber
WindowsClient.net WPF Training Videos
MVVM ...
Oracle SQL Query for listing all Schemas in a DB
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@Andy: that's why I wrote "as a privileged user" ;)
– a_horse_with_no_name
Jan 28 '11 at 23:01
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How to undo 'git reset'?
...list is the commit that you lost. Let's say you just typed git reset HEAD~ and want to undo it. My reflog looks like this:
$ git reflog
3f6db14 HEAD@{0}: HEAD~: updating HEAD
d27924e HEAD@{1}: checkout: moving from d27924e0fe16776f0d0f1ee2933a0334a4787b4c
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The first line says that HEAD 0 pos...
Running a cron every 30 seconds
...e offset by 30 seconds:
# Need these to run on 30-sec boundaries, keep commands in sync.
* * * * * /path/to/executable param1 param2
* * * * * ( sleep 30 ; /path/to/executable param1 param2 )
You'll see I've added comments and formatted to ensure it's easy to keep them synchronised.
Bo...
Read only the first line of a file?
...ile again when the block ends.
The with statement only works in Python 2.5 and up, and in Python 2.5 you need to use from __future__ import with_statement
In Python 3 you should specify the file encoding for the file you open. Read more...
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Convert an array of primitive longs into a List of Longs
...y completely failed to work. I wanted to take an array of primitive longs and turn it into a list, which I attempted to do like this:
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Why is rbindlist “better” than rbind?
I am going through documentation of data.table and also noticed from some of the conversations over here on SO that rbindlist is supposed to be better than rbind .
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