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Best way of returning a random boolean value
...alse].sample is faster than rand(2) == 1. When I performed each operation 10 million times the rand method was 2.179s. The sample method was 1.645s.
– Mirror318
Jun 27 '16 at 4:47
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Java String - See if a string contains only numbers and not letters
...Z]+") == false && text.length() > 2){
to:
if (text.matches("[0-9]+") && text.length() > 2) {
Instead of checking that the string doesn't contain alphabetic characters, check to be sure it contains only numerics.
If you actually want to use the numeric value, use Integer.p...
C# 5 async CTP: why is internal “state” set to 0 in generated code before EndAwait call?
...t. Many thanks to him - and please visit his blog, which rocks.
The value 0 here is only special because it's not a valid state which you might be in just before the await in a normal case. In particular, it's not a state which the state machine may end up testing for elsewhere. I believe that usin...
Why is GHC so large/big?
... |
edited Feb 1 '11 at 20:04
answered Feb 1 '11 at 19:48
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Is there a way to list pip dependencies/requirements?
...m providing an updated answer.
This was tested with pip versions 8.1.2, 9.0.1, 10.0.1, and 18.1.
To get the output without cluttering your current directory on Linux use
pip download [package] -d /tmp --no-binary :all: -v
-d tells pip the directory that download should put files in.
Better, ju...
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...
Does Python support short-circuiting?
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answered Apr 5 '10 at 18:20
Alex MartelliAlex Martelli
724k148148 gold badges11251125 silver badges13241324 bronze badges
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How to get different colored lines for different plots in a single figure?
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E.g.:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.show()
And, as you may already know, you can easily add a legend:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt...
How to create custom easing function with Core Animation?
...tric.h:
// this should be a function that takes a time value between
// 0.0 and 1.0 (where 0.0 is the beginning of the animation
// and 1.0 is the end) and returns a scale factor where 0.0
// would produce the starting value and 1.0 would produce the
// ending value
typedef double (^KeyframePa...
Javascript seconds to minutes and seconds
...
To get the number of full minutes, divide the number of total seconds by 60 (60 seconds/minute):
var minutes = Math.floor(time / 60);
And to get the remaining seconds, multiply the full minutes with 60 and subtract from the total seconds:
var seconds = time - minutes * 60;
Now if you also wan...