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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ld instances (at least,
not at the moment). If a base class has a field called author, you
cannot create another model field called author in any class that
inherits from that base class.
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Tracking the script execution time in PHP
...";
echo "It spent " . rutime($ru, $rustart, "stime") .
" ms in system calls\n";
Note that you don't need to calculate a difference if you are spawning a php instance for every test.
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How do I convert a String object into a Hash object?
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The string created by calling Hash#inspect can be turned back into a hash by calling eval on it. However, this requires the same to be true of all of the objects in the hash.
If I start with the hash {:a => Object.new}, then its string represen...
How to determine whether a given Linux is 32 bit or 64 bit?
...wk '{print $2}'
Note: you can have a 64-bit CPU with a 32-bit kernel installed.
(as ysdx mentions in his/her own answer, "Nowadays, a system can be multiarch so it does not make sense anyway. You might want to find the default target of the compiler")
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Queue.Queue vs. collections.deque
...nd collections.deque serve different purposes. Queue.Queue is intended for allowing different threads to communicate using queued messages/data, whereas collections.deque is simply intended as a datastructure. That's why Queue.Queue has methods like put_nowait(), get_nowait(), and join(), whereas co...
Delete column from SQLite table
...the columns, whereas something like the accepted answer seems to result in all columns to be of type TEXT.
– Uwe Keim
Jul 10 '17 at 15:05
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Set select option 'selected', by value
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I had to manually call .val(x).change(); to trigger the select's onChange event, it seems setting val() doesn't fire it.
– scipilot
Jul 19 '15 at 5:48
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Circle line-segment collision detection algorithm?
... exdx + eydy - dxh - dyk ) +
ex2 + ey2 -
2exh - 2eyk + h2 + k2 - r2 = 0
Finally,
t2( _d * _d ) + 2t( _e * _d - _d * _c ) + _e * _e - 2( _e*_c ) + _c * _c - r2 = 0
*Where _d is the vector d and * is the dot product.*
And then,
t2( _d * _d ) + 2t( _d * ( _e - _c ) ) + ( _e - _c ) * ( _e - _c ) - r2 = ...
In-memory size of a Python structure
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Yep. The "4 higher" actually mostly look like "rounding up to a multiple of 8" which I believe is correct for the way malloc behaves here. No idea why decimal gets so distorted (with pympler on 2.6, too).
– Alex Martelli
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Reset Entity-Framework Migrations
... I used IgnoreChanges on the initial migration, but now I want to delete all my migrations and start with an initial migration with all of the logic.
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