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Numbering rows within groups in a data frame
Working with a data frame similar to this:
7 Answers
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Set every cell in matrix to 0 if that row or column contains a 0
Given a NxN matrix with 0s and 1s. Set every row that contains a 0 to all 0 s and set every column that contains a 0 to all 0 s.
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pandas DataFrame: replace nan values with average of columns
I've got a pandas DataFrame filled mostly with real numbers, but there is a few nan values in it as well.
10 Answers
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Why does ('0' ? 'a' : 'b') behave different than ('0' == true ? 'a' : 'b') [duplicate]
Why is the result of the following two statements different?
6 Answers
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Reduce, fold or scan (Left/Right)?
When should I use reduceLeft , reduceRight , foldLeft , foldRight , scanLeft or scanRight ?
3 Answers
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How to make an OpenGL rendering context with transparent background?
Rendering contexts usually have a solid color on the background (black or whatever, see the image below):
9 Answers
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How do I create an average from a Ruby array?
How would get find an average from an array?
20 Answers
20
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Creating a CSS3 box-shadow on all sides but one
I've got a tabbed navigation bar where I'd like the open tab to have a shadow to set it apart from the other tabs. I'd also like the whole tab section to have a single shadow (see bottom horizontal line) going up, shading the bottom of all tabs except for the open one.
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Center a map in d3 given a geoJSON object
Currently in d3 if you have a geoJSON object that you are going to draw you have to scale it and translate it in order to get it to the size that one wants and translate it in order to center it. This is a very tedious task of trial and error, and I was wondering if anyone knew a better way to obtai...
Sorting arrays in NumPy by column
How can I sort an array in NumPy by the nth column?
13 Answers
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