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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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Parse usable Street Address, City, State, Zip from a string [closed]
...ase which has been converted to Sql Server 2005. This field has everything all in one field. I need to parse out the individual sections of the address into their appropriate fields in a normalized table. I need to do this for approximately 4,000 records and it needs to be repeatable.
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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...
Are arrays passed by value or passed by reference in Java? [duplicate]
...a primitive type in Java, but they are not objects either ... "
In fact, all arrays in Java are objects1. Every Java array type has java.lang.Object as its supertype, and inherits the implementation of all methods in the Object API.
... so are they passed by value or by reference? Does it de...
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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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....
How to save a plot as image on the disk?
...d like to save that image as PNG or JPEG, is it possible to do it automatically? (via code)
11 Answers
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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...