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How to access the ith column of a NumPy multidimensional array?
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>>> test[:,0]
array([1, 3, 5])
Similarly,
>>> test[1,:]
array([3, 4])
lets you access rows. This is covered in Section 1.4 (Indexing) of the NumPy reference. This is quick, at least in my experience. It's certainly much quicker tha...
Javascript calculate the day of the year (1 - 366)
How do I use javascript to calculate the day of the year, from 1 - 366? For example:
22 Answers
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Memoization in Haskell?
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f mf 0 = 0
f mf n = max n $ mf (n `div` 2) +
mf (n `div` 3) +
mf (n `div` 4)
You can get an unmemoized f by using fix f
This will let you test that f does what you mean for small values of f by calling, for example: fix f 123 = 144
We could memoize this by def...
List comprehension on a nested list?
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332
Here is how you would do this with a nested list comprehension:
[[float(y) for y in x] for x ...
Two-dimensional array in Swift
...ray of arrays of Ints set to 0. Arrays size is 10x5
var arr = Array(count: 3, repeatedValue: Array(count: 2, repeatedValue: 0))
// ...and for Swift 3+:
var arr = Array(repeating: Array(repeating: 0, count: 2), count: 3)
Change element at position
arr[0][1] = 18
OR
let myVar = 18
arr[0][1] = m...
Could not load file or assembly 'Newtonsoft.Json, Version=4.5.0.0, Culture=neutral, PublicKeyToken=3
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edited May 19 '16 at 12:31
s_a
16322 silver badges44 bronze badges
answered Apr 30 '14 at 7:00
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How to find the installed pandas version
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375
Check pandas.__version__:
In [76]: import pandas as pd
In [77]: pd.__version__
Out[77]: '0.1...
What Process is using all of my disk IO
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edited Dec 7 '14 at 14:13
Aaron Digulla
288k9494 gold badges528528 silver badges757757 bronze badges
a...
How to take column-slices of dataframe in pandas
...ing to 'bar'
df.loc[:, :'bar']
# foo bar
# slice from 'quz' to the end by 3
df.loc[:, 'quz'::3]
# quz sat
# attempt from 'sat' to 'bar'
df.loc[:, 'sat':'bar']
# no columns returned
# slice from 'sat' to 'bar'
df.loc[:, 'sat':'bar':-1]
sat cat ant quz bar
# slice notation is syntatic sugar for th...
Formula to determine brightness of RGB color
... → sqrt( 0.299*R^2 + 0.587*G^2 + 0.114*B^2 ) (thanks to @MatthewHerbst) [3]
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