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What does a tilde do when it precedes an expression?
...rator that flips all bits in its operand.
For example, if your number was 1, its binary representation of the IEEE 754 float (how JavaScript treats numbers) would be...
0011 1111 1111 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
So ~ converts its operand to a 32 bit integer (...
List distinct values in a vector in R
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169
Do you mean unique:
R> x = c(1,1,2,3,4,4,4)
R> x
[1] 1 1 2 3 4 4 4
R> unique(x)
[1] ...
How do I generate random number for each row in a TSQL Select?
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19 Answers
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Useful code which uses reduce()? [closed]
...n Scheme a lot...
Here's some cute usages:
Flatten a list
Goal: turn [[1, 2, 3], [4, 5], [6, 7, 8]] into [1, 2, 3, 4, 5, 6, 7, 8].
reduce(list.__add__, [[1, 2, 3], [4, 5], [6, 7, 8]], [])
List of digits to a number
Goal: turn [1, 2, 3, 4, 5, 6, 7, 8] into 12345678.
Ugly, slow way:
int("".j...
Difference between Pragma and Cache-Control headers?
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198
Pragma is the HTTP/1.0 implementation and cache-control is the HTTP/1.1 implementation of the ...
Remove duplicate values from JS array [duplicate]
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Python matplotlib multiple bars
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112
import matplotlib.pyplot as plt
from matplotlib.dates import date2num
import datetime
x = [
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Using module 'subprocess' with timeout
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177
In Python 3.3+:
from subprocess import STDOUT, check_output
output = check_output(cmd, stder...
python pandas dataframe to dictionary
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Remove an item from a dictionary when its key is unknown
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10 Answers
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