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how to mysqldump remote db from local machine
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250
As I haven't seen it at serverfault yet, and the answer is quite simple:
Change:
ssh -f -L331...
Apply a function to every row of a matrix or a data frame
..., byrow=TRUE)
R> M
[,1] [,2]
[1,] 1 2
[2,] 3 4
[3,] 5 6
R> apply(M, 1, function(x) 2*x[1]+x[2])
[1] 4 10 16
R>
This takes a matrix and applies a (silly) function to each row. You pass extra arguments to the function as fourth, fifth, ... arguments to apply().
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How to compare strings ignoring the case
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5 Answers
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python pandas remove duplicate columns
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Jean-François Corbett
33.6k2525 gold badges124124 silver badges172172 bronze badges
answered Nov 5 '16 at 6:15
Gene BurinskyGene ...
What does the constant 0.0039215689 represent?
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0.0039215689 is approximately equal to 1/255.
Seeing that this is OpenGL, performance is probably important. So it's probably safe to guess that this was done for performance reasons.
Multiplying by the reciprocal is faster than re...
What does numpy.random.seed(0) do?
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598
np.random.seed(0) makes the random numbers predictable
>>> numpy.random.seed(0) ; nu...
How to get the first column of a pandas DataFrame as a Series?
...pandas as pd
>>> df = pd.DataFrame({'x' : [1, 2, 3, 4], 'y' : [4, 5, 6, 7]})
>>> df
x y
0 1 4
1 2 5
2 3 6
3 4 7
>>> s = df.ix[:,0]
>>> type(s)
<class 'pandas.core.series.Series'>
>>>
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Most efficient way to create a zero filled JavaScript array?
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582
ES6 introduces Array.prototype.fill. It can be used like this:
new Array(len).fill(0);
Not ...