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How do I compute derivative using Numpy?
...n [2]: import numpy as np
In [3]: x = Symbol('x')
In [4]: y = x**2 + 1
In [5]: yprime = y.diff(x)
In [6]: yprime
Out[6]: 2⋅x
In [7]: f = lambdify(x, yprime, 'numpy')
In [8]: f(np.ones(5))
Out[8]: [ 2. 2. 2. 2. 2.]
sh...
Find value in an array
..., and if that's the case, you can use Array#include?(value):
a = [1,2,3,4,5]
a.include?(3) # => true
a.include?(9) # => false
If you mean something else, check the Ruby Array API
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Reference — What does this symbol mean in PHP?
...is a byte? A byte is made up of 8 bits and the highest value of a byte is 255, which would mean every bit is set. We will look at why a byte's maximum value is 255.
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| 1 Byte ( 8 bits ) |
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|P...
How to sort an array of associative arrays by value of a given key in PHP?
...row['price'];
}
array_multisort($price, SORT_DESC, $inventory);
As of PHP 5.5.0 you can use array_column() instead of that foreach:
$price = array_column($inventory, 'price');
array_multisort($price, SORT_DESC, $inventory);
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Most efficient way to reverse a numpy array
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answered Jul 21 '11 at 5:25
stevehasteveha
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Can I split an already split hunk with git?
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If you're using git add -p and even after splitting with s, you don't have a small enough chang...
Error message Strict standards: Non-static method should not be called statically in php
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edited Jun 13 '17 at 12:59
Andy Mercer
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answere...
npm can't find package.json
I'm trying to install the dependencies of some example: npm's express 2.5.8 that I've downloaded, but all of the apps throw the same error:
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How do I get the current date and time in PHP?
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edited Aug 15 '14 at 21:06
Steve Chambers
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mysql error 1364 Field doesn't have a default values
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zardilior
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answered Mar 15 '13 at 17:47
KinSlayerUYKinSlayerUY
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