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Iterating over a numpy array
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188
I think you're looking for the ndenumerate.
>>> a =numpy.array([[1,2],[3,4],[5,6]])
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What is the difference between join and merge in Pandas?
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import pandas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l val_r
key
foo 1 4
bar 2 5
The ...
Inspecting standard container (std::map) contents with gdb
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answered Jan 9 '09 at 10:31
jpalecekjpalecek
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How can I determine whether a 2D Point is within a Polygon?
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SQL Server : Columns to Rows
...from yourtable
unpivot
(
indicatorvalue
for indicatorname in (Indicator1, Indicator2, Indicator3)
) unpiv;
Note, the datatypes of the columns you are unpivoting must be the same so you might have to convert the datatypes prior to applying the unpivot.
You could also use CROSS APPLY with UNIO...
How to sort a dataframe by multiple column(s)
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19 Answers
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Speed up the loop operation in R
...on). The data.frame has roughly 850K rows. My PC is still working (about 10h now) and I have no idea about the runtime.
1...
How do you know when to use fold-left and when to use fold-right?
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105
You can transfer a fold into an infix operator notation (writing in between):
This example fo...
Commenting multiple lines in DOS batch file
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185
You can use a goto to skip over code.
goto comment
...skip this...
:comment
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How to determine if a list of polygon points are in clockwise order?
... telling you whether it's mostly clockwise).
Sum over the edges, (x2 − x1)(y2 + y1). If the result is positive the curve is clockwise, if it's negative the curve is counter-clockwise. (The result is twice the enclosed area, with a +/- convention.)
point[0] = (5,0) edge[0]: (6-5)(4+0) = 4
poi...