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Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
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@KonradGadzina: Strict equals will make all three functions return false.
– Jon
May 9 '14 at 10:18
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Principal component analysis in Python
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Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
Rotating videos with FFmpeg
...ine).
Note that this will re-encode the audio and video parts. You can usually copy the audio without touching it, by using -c:a copy. To change the video quality, set the bitrate (for example with -b:v 1M) or have a look at the H.264 encoding guide if you want VBR options.
A solution is also to u...
Is explicitly closing files important?
In Python, if you either open a file without calling close() , or close the file but not using try - finally or the " with " statement, is this a problem? Or does it suffice as a coding practice to rely on the Python garbage-collection to close all files? For example, if one does this:
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How to revert a Git Submodule pointer to the commit stored in the containing repository?
...or the key submodule.$name.update
is set to rebase or merge.
Run this and all should be well:
git submodule update --init
You can add the --recursive flag as well to recurse through all submodules.
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Why is the shovel operator (
...ut who has to clean the glass and more about the number of glasses used at all. You could imagine that certain applications are pushing the limits of memory on their machines and that those machines can only clean a certain number of glasses at a time.
– Charlie L
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Difference between map and collect in Ruby?
I have Googled this and got patchy / contradictory opinions - is there actually any difference between doing a map and doing a collect on an array in Ruby/Rails?
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Action bar navigation modes are deprecated in Android L
...king a look at the API diff report for the Android "L" preview, I see that all methods related to navigation modes in the ActionBar class (such as setNavigationMode() , addTab() , selectTab() , &c). are now deprecated.
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What are JavaScript's builtin strings?
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First of all, I would like to thank Jason and all the contributors for playing with that funny snippet. I have written that piece of code just for fun in order to send it to my wife on February 14 :) Having only Chrome installed on th...
The difference between sys.stdout.write and print?
...ble, but by default with a space between args and newline at the end) and calls the write function of a given object. By default this object is sys.stdout, but you can pass a file using the "chevron" form. For example:
print >> open('file.txt', 'w'), 'Hello', 'World', 2+3
See: https://docs....