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Python integer division yields float
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answered Aug 15 '09 at 21:51
Brandon E TaylorBrandon E Taylor
23.1k66 gold badges4343 silver badges6868 bronze badges
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How to count the number of true elements in a NumPy bool array
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>>> import numpy as np
>>> boolarr = np.array([[0, 0, 1], [1, 0, 1], [1, 0, 1]], dtype=np.bool)
>>> boolarr
array([[False, False, True],
[ True, False, True],
[ True, False, True]], dtype=bool)
>>> np.sum(boolarr)
5
Of course, that is a bool...
Syntax for creating a two-dimensional array
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12 Answers
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Selecting with complex criteria from pandas.DataFrame
...; from random import randint
>>> df = pd.DataFrame({'A': [randint(1, 9) for x in range(10)],
'B': [randint(1, 9)*10 for x in range(10)],
'C': [randint(1, 9)*100 for x in range(10)]})
>>> df
A B C
0 9 40 300
1 9 70 700
2 5 70 90...
Grep regex NOT containing string
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351
grep matches, grep -v does the inverse. If you need to "match A but not B" you usually use pipes...
How to remove element from an array in JavaScript?
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12 Answers
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Remove empty elements from an array in Javascript
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How to filter a dictionary according to an arbitrary condition function?
... comprehension:
{k: v for k, v in points.iteritems() if v[0] < 5 and v[1] < 5}
And in Python 3:
{k: v for k, v in points.items() if v[0] < 5 and v[1] < 5}
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How to not run an example using roxygen2?
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147
Use \dontrun{}
#'@examples
#'\dontrun{
#'geocode("3817 Spruce St, Philadelphia, PA 19104")
#'...
How assignment works with Python list slice?
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116
You are confusing two distinct operation that use very similar syntax:
1) slicing:
b = a[0:2...