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How to count certain elements in array?
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How to check whether a pandas DataFrame is empty?
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edited Dec 15 '17 at 17:37
Dave Thomas
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What's the difference between integer class and numeric class in R
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answered May 14 '14 at 17:07
Greg SnowGreg Snow
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MySQL IF NOT NULL, then display 1, else display 0
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214
Instead of COALESCE(a.addressid,0) AS addressexists, use CASE:
CASE WHEN a.addressid IS NOT NU...
stash@{1} is ambiguous?
...et info about my stash, but git is telling me that stash@{0} and stash@{1} are ambiguous. git stash list works fine, and .git/logs/refs/stash seems to have the appropriate content (not that I'm an expert on git internals).
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adding noise to a signal in python
I want to add some random noise to some 100 bin signal that I am simulating in Python - to make it more realistic.
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Syntax for creating a two-dimensional array
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How to get row from R data.frame
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130
x[r,]
where r is the row you're interested in. Try this, for example:
#Add your data
x <...
Printf width specifier to maintain precision of floating-point value
... in:
#include <float.h>
int Digs = DECIMAL_DIG;
double OneSeventh = 1.0/7.0;
printf("%.*e\n", Digs, OneSeventh);
// 1.428571428571428492127e-01
But let's dig deeper ...
Mathematically, the answer is "0.142857 142857 142857 ...", but we are using finite precision floating point numbers.
L...
Regular expression search replace in Sublime Text 2
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Usually a back-reference is either $1 or \1 (backslash one) for the first capture group (the first match of a pattern in parentheses), and indeed Sublime supports both syntaxes. So try:
my name used to be \1
or
my name used to be $1
Also note that your or...