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How do you do a ‘Pause’ with PowerShell 2.0?
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edited Dec 27 '14 at 14:54
Peter Mortensen
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Breaking a list into multiple columns in Latex
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4 Answers
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Multiple levels of 'collection.defaultdict' in Python
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347
Use:
from collections import defaultdict
d = defaultdict(lambda: defaultdict(int))
This will...
How do you get the magnitude of a vector in Numpy?
...y -- say x.norm() -- but oh well).
import numpy as np
x = np.array([1,2,3,4,5])
np.linalg.norm(x)
You can also feed in an optional ord for the nth order norm you want. Say you wanted the 1-norm:
np.linalg.norm(x,ord=1)
And so on.
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Column order manipulation using col-lg-push and col-lg-pull in Twitter Bootstrap 3
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284
This answer is in three parts, see below for the official release (v3 and v4)
I couldn't even f...
How to convert a boolean array to an int array
...[ True, False, True], dtype=bool)
>>> x + [1, 2, 3]
array([2, 2, 4])
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Does Ruby regular expression have a not match operator like “!~” in Perl?
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answered Dec 7 '12 at 8:04
Konrad RudolphKonrad Rudolph
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Python - When to use file vs open
...el this way when the obvious intent of the devs back then was 2 retain open4compat.
– umeboshi
Sep 21 '13 at 17:35
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What does .SD stand for in data.table in R
...,3), v=1:6)
setkey(DT, y)
DT
# x y v
# 1: a 1 1
# 2: b 1 3
# 3: c 1 5
# 4: a 3 2
# 5: b 3 4
# 6: c 3 6
Doing this may help you see what .SD is:
DT[ , .SD[ , paste(x, v, sep="", collapse="_")], by=y]
# y V1
# 1: 1 a1_b3_c5
# 2: 3 a2_b4_c6
Basically, the by=y statement breaks the orig...