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How to set default value for form field in Symfony2?
..., it will also always force the value under any context. Not what I would call a "default value"...
– Hubert Perron
Apr 3 '13 at 18:25
4
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How to determine the encoding of text?
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Correctly detecting the encoding all times is impossible.
(From chardet FAQ:)
However, some encodings are optimized
for specific languages, and languages
are not random. Some character
sequences pop up all the time, while
other sequences make no...
What's the difference between the atomic and nonatomic attributes?
...o are identical; "atomic" is the default behavior (note that it is not actually a keyword; it is specified only by the absence of nonatomic -- atomic was added as a keyword in recent versions of llvm/clang).
Assuming that you are @synthesizing the method implementations, atomic vs. non-atomic chang...
Why is pow(a, d, n) so much faster than a**d % n?
...was taking so long (> 20 seconds) for midsize numbers (~7 digits). I eventually found the following line of code to be the source of the problem:
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Exception messages in English?
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This issue can be partially worked around. The Framework exception code loads the error messages from its resources, based on the current thread locale. In the case of some exceptions, this happens at the time the Message property is accessed.
For...
How to crop an image in OpenCV using Python
...copy region of interest
If we consider (0,0) as top left corner of image called im with left-to-right as x direction and top-to-bottom as y direction. and we have (x1,y1) as the top-left vertex and (x2,y2) as the bottom-right vertex of a rectangle region within that image, then:
roi = im[y1:y2, x1...
Simple argparse example wanted: 1 argument, 3 results
...or meddle with formatting lines on the screen or change option characters. All I want to do is "If arg is A, do this, if B do that, if none of the above show help and quit" .
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Unioning two tables with different number of columns
... I realized that this solution also works without having to list all the columns. So instead of Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2, one can also do, Select *, Null as Col4, Null as Col5 from Table2.
– Pratik Patel
Sep 20 '...
Run certain code every n seconds [duplicate]
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This seems not to resolve the question at all... it does not repeat every second.
– Yan King Yin
Jul 5 '13 at 15:28
9
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MySQL, Check if a column exists in a table with SQL
...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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