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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...ntents of True. In other words, True is reassignable:
Python 2.7 (r27:82508, Jul 3 2010, 21:12:11)
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> True = 4
>>> True
4
In Python 3.x it truly becomes a k...
Selecting data frame rows based on partial string match in a column
...
150
I notice that you mention a function %like% in your current approach. I don't know if that's a r...
What Are the Differences Between PSR-0 and PSR-4?
.... However, I can't seem to grasp what the actual difference is between PSR-0 and PSR-4.
5 Answers
...
Android studio: new project vs new module
...
102
From the documentation (Android Studio is based on Intellij IDEA) :
Whatever you do in Inte...
Return index of greatest value in an array
... works on old browsers:
function indexOfMax(arr) {
if (arr.length === 0) {
return -1;
}
var max = arr[0];
var maxIndex = 0;
for (var i = 1; i < arr.length; i++) {
if (arr[i] > max) {
maxIndex = i;
max = arr[i];
}
}
...
How to create a video from images with FFmpeg?
...video filter instead of -r for the output framerate
ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4
Alternatively the format video filter can be added to the filter chain to replace -pix_fmt yuv420p like "fps=25,format=yuv420p". The advantage of this method is th...
surface plots in matplotlib
...t.figure()
ax = fig.add_subplot(111, projection='3d')
x = y = np.arange(-3.0, 3.0, 0.05)
X, Y = np.meshgrid(x, y)
zs = np.array(fun(np.ravel(X), np.ravel(Y)))
Z = zs.reshape(X.shape)
ax.plot_surface(X, Y, Z)
ax.set_xlabel('X Label')
ax.set_ylabel('Y Label')
ax.set_zlabel('Z Label')
plt.show()
...
php is null or empty?
...LL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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Adding 'serial' to existing column in Postgres
I have a small table (~30 rows) in my Postgres 9.0 database with an integer ID field (the primary key) which currently contains unique sequential integers starting at 1, but which was not created using the 'serial' keyword.
...
C++: Rounding up to the nearest multiple of a number
...ger math.
int roundUp(int numToRound, int multiple)
{
if (multiple == 0)
return numToRound;
int remainder = numToRound % multiple;
if (remainder == 0)
return numToRound;
return numToRound + multiple - remainder;
}
Edit: Here's a version that works with negative n...