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How to force composer to reinstall a library?
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7 Answers
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How can I apply a function to every row/column of a matrix in MATLAB?
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73
Many built-in operations like sum and prod are already able to operate across rows or columns, ...
How can I convert an RGB image into grayscale in Python?
...'greyscale.png')
Using matplotlib and the formula
Y' = 0.2989 R + 0.5870 G + 0.1140 B
you could do:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
def rgb2gray(rgb):
return np.dot(rgb[...,:3], [0.2989, 0.5870, 0.1140])
img = mpimg.imread('image.png...
What is the purpose of “return await” in C#?
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String concatenation in Ruby
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scarver2
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answered Dec 18 '08 at 13:09
KeltiaKeltia
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Indentation shortcuts in Visual Studio
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Mike ChristensenMike Christensen
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Get protocol + host name from URL
...# Python 2
parsed_uri = urlparse('http://stackoverflow.com/questions/1234567/blah-blah-blah-blah' )
result = '{uri.scheme}://{uri.netloc}/'.format(uri=parsed_uri)
print(result)
# gives
'http://stackoverflow.com/'
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`require': no such file to load — mkmf (LoadError)
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979
After some search for a solution it turns out the -dev package is needed, not just ruby1.8. So ...
How to cast Object to its actual type?
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answered Sep 2 '12 at 7:22
Marc Gravell♦Marc Gravell
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