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Boolean literals in PowerShell
...ts are true, for example. null, empty strings, empty arrays and the number 0 are false.
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How to initialize all members of an array to the same value in Swift?
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170
Actually, it's quite simple with Swift. As mentioned in the Apple's doc, you can initialize an a...
Java regular expression OR operator
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edited Jan 9 '10 at 0:57
answered Jan 9 '10 at 0:46
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How can I convert an RGB image into grayscale in Python?
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320
How about doing it with Pillow:
from PIL import Image
img = Image.open('image.png').convert('LA...
How do you validate a URL with a regular expression in Python?
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answered May 6 '09 at 1:09
S.LottS.Lott
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Better way to shuffle two numpy arrays in unison
...ple: Let's assume the arrays a and b look like this:
a = numpy.array([[[ 0., 1., 2.],
[ 3., 4., 5.]],
[[ 6., 7., 8.],
[ 9., 10., 11.]],
[[ 12., 13., 14.],
[ 15., 16., 17.]]])
b = numpy.a...
“x not in y” or “not x in y”
... 'ham' not in 'spam and eggs'
>>> dis.dis(notin)
2 0 LOAD_CONST 1 ('ham')
3 LOAD_CONST 2 ('spam and eggs')
6 COMPARE_OP 7 (not in)
9 POP_TOP
10 LOAD_CONST ...
Design patterns or best practices for shell scripts [closed]
...-s bash -o c:d:: --long config_file:,debug_level:: -- "$@"`
if test $? != 0
then
echo "unrecognized option"
exit 1
fi
eval set -- "$getopt_results"
while true
do
case "$1" in
--config_file)
CommandLineOptions__config_file="$2";
shift 2;
;;
...
How to shift a column in Pandas DataFrame
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In [18]: a
Out[18]:
x1 x2
0 0 5
1 1 6
2 2 7
3 3 8
4 4 9
In [19]: a.x2 = a.x2.shift(1)
In [20]: a
Out[20]:
x1 x2
0 0 NaN
1 1 5
2 2 6
3 3 7
4 4 8
...
What is the Scala annotation to ensure a tail recursive function is optimized?
...ps and tricks):
C:\Prog\Scala\tests>scala
Welcome to Scala version 2.8.0.RC5 (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_18).
Type in expressions to have them evaluated.
Type :help for more information.
scala> import scala.annotation.tailrec
import scala.annotation.tailrec
scala> clas...