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How can I save an image with PIL?
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edited Jul 27 at 21:34
Abhishek kumar
10366 bronze badges
answered Jan 23 '13 at 3:42
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How to create a temporary directory and get the path / file name in Python
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Samuel Rossille
16k1818 gold badges5353 silver badges8282 bronze badges
answered Jul 11 '10 at 15:45
PhilippPhilipp
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How to check whether a file is empty or not?
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361
>>> import os
>>> os.stat("file").st_size == 0
True
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What is the difference between NaN and None?
...= pd.Series([1, None], dtype=object)
s_good = pd.Series([1, np.nan])
In [13]: s_bad.dtype
Out[13]: dtype('O')
In [14]: s_good.dtype
Out[14]: dtype('float64')
Jeff comments (below) on this:
np.nan allows for vectorized operations; its a float value, while None, by definition, forces object ty...
Using the Swift if let with logical AND operator &&
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As of Swift 1.2, this is now possible. The Swift 1.2 and Xcode 6.3 beta release notes state:
More powerful optional unwrapping with if let — The if let construct
can now unwrap multiple optionals at once, as well as include
intervening boolean conditions. This lets you express co...
How to wait for 2 seconds?
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378
The documentation for WAITFOR() doesn't explicitly lay out the required string format.
This...
How can sbt pull dependency artifacts from git?
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answered Sep 26 '11 at 3:40
Kipton BarrosKipton Barros
19.7k33 gold badges6161 silver badges7575 bronze badges
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Performance - Date.now() vs Date.getTime()
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edited Oct 29 '13 at 19:28
kevinji
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ans...
Rails hidden field undefined method 'merge' error
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– Augustin Riedinger
Sep 24 '14 at 13:30
add a comment
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Rails 3 check if attribute changed
Need to check if a block of attributes has changed before update in Rails 3.
5 Answers
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