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How do I get bit-by-bit data from an integer value in C?

...wanted){ int *bits = malloc(sizeof(int) * bitswanted); int k; for(k=0; k<bitswanted; k++){ int mask = 1 << k; int masked_n = n & mask; int thebit = masked_n >> k; bits[k] = thebit; } return bits; } int main(){ int n=7; int bitswanted = 5; int...
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Sample random rows in dataframe

... 460 First make some data: > df = data.frame(matrix(rnorm(20), nrow=10)) > df X1 ...
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In Python, how do I convert all of the items in a list to floats?

... 470 [float(i) for i in lst] to be precise, it creates a new list with float values. Unlike the map...
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What is the significance of initializing direction arrays below with given values when developing ch

... want to add onto its x and its y value to move it to a nearby location, 1,0 is east, -1,0 is west, 0,1 is south, 0,-1 is north and so on. (Here I have said top left is 0,0 and bottom right is 4,4 and shown what move each index of the arrays will make from the central point, X, at 2,2.) ..... .536...
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How to get the source directory of a Bash script from within the script itself?

... #!/bin/bash DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )" is a useful one-liner which will give you the full directory name of the script no matter where it is being called from. It will work as long as the last component of the p...
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How to remove gaps between subplots in matplotlib?

... 103 You can use gridspec to control the spacing between axes. There's more information here. impo...
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how to use sed, awk, or gawk to print only what is matched?

... tried * instead and I added p tag for printing match: sed -n 's/^.*abc\([0-9]*\)xyz.*$/\1/p' example.txt For matching at least one numeric character without +, I would use: sed -n 's/^.*abc\([0-9][0-9]*\)xyz.*$/\1/p' example.txt ...
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How to validate an email address using a regular expression?

... +50 The fully RFC 822 compliant regex is inefficient and obscure because of its length. Fortunately, RFC 822 was superseded twice and the...
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How to truncate the time on a DateTime object in Python?

... 390 I think this is what you're looking for... >>> import datetime >>> dt = datet...
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Pandas groupby: How to get a union of strings

..._csv(StringIO(data),sep='\s+') In [5]: df Out[5]: A B C 0 1 0.749065 This 1 2 0.301084 is 2 3 0.463468 a 3 4 0.643961 random 4 1 0.866521 string 5 2 0.120737 ! In [6]: df.dtypes Out[6]: A int64 B float64 C object dtype: object When...