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Convert data.frame column to a vector?
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8
[..., drop = F] will always return a data frame
– hadley
Aug 16 '11 at 18:19
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Boolean vs tinyint(1) for boolean values in MySQL
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edited Dec 15 '15 at 18:21
answered Sep 20 '10 at 13:26
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Access object child properties using a dot notation string [duplicate]
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answered Nov 8 '11 at 14:39
Andy EAndy E
300k7575 gold badges456456 silver badges436436 bronze badges
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What is the Invariant Culture?
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answered Mar 11 '10 at 8:05
Andrew BezzubAndrew Bezzub
14.5k66 gold badges4444 silver badges6767 bronze badges
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Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize
When building a Java 8 project with Maven:
8 Answers
8
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Add column with constant value to pandas dataframe [duplicate]
...with partially aligned indices:
In [7]: from pandas import DataFrame
In [8]: from numpy.random import randint
In [9]: df = DataFrame({'a': randint(3, size=10)})
In [10]:
In [10]: df
Out[10]:
a
0 0
1 2
2 0
3 1
4 0
5 0
6 0
7 0
8 0
9 0
In [11]: s = df.a[:5]
In [12]: dfa, sa = df.ali...
Version of Apache installed on a Debian machine
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418
Try apachectl -V:
$ apachectl -V
Server version: Apache/2.2.9 (Unix)
Server built: Sep 18 200...
What is the difference between an int and a long in C++?
... 4 bytes
Linux IA-32 4 bytes
Linux Intel 64 8 bytes
Linux IA-64 8 bytes
Mac OS X IA-32 4 bytes
Mac OS X Intel 64 8 bytes
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Integer.valueOf() vs. Integer.parseInt() [duplicate]
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nyg
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answered Sep 8 '11 at 22:00
corsiKacorsiKa
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Finding median of list in Python
...> median([1, 3, 5, 7])
4.0
Usage:
import statistics
items = [6, 1, 8, 2, 3]
statistics.median(items)
#>>> 3
It's pretty careful with types, too:
statistics.median(map(float, items))
#>>> 3.0
from decimal import Decimal
statistics.median(map(Decimal, items))
#>>&g...