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How to select where ID in Array Rails ActiveRecord without exception
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If it is just avoiding the exception you are worried about, the "find_all_by.." family of functions works without throwing exceptions.
Comment.find_all_by_id([2, 3, 5])
will work even if some of the ids don't exist. This works in the
user.comments.find_all_by_id(potentially_nonexistent_id...
How does python numpy.where() work?
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How do they achieve internally that you are able to pass something like x > 5 into a method?
The short answer is that they don't.
Any sort of logical operation on a numpy array returns a boolean array. (i.e. __gt__, __lt__, etc all return boolea...
How can I swap positions of two open files (in splits) in vim?
... 'hide buf' markedBuf
endfunction
nmap <silent> <leader>mw :call MarkWindowSwap()<CR>
nmap <silent> <leader>pw :call DoWindowSwap()<CR>
To use (assuming your mapleader is set to \) you would:
Move to the window to mark for the swap via
ctrl-w movement
Type ...
A python class that acts like dict
...er) instead of simply delegating to the instance's __dict__ - which essentially means you're creating two dicts for every instance.
– Aaron Hall♦
Jan 8 '17 at 0:39
8
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How to add a custom loglevel to Python's logging facility
...for my application, as I don't think that debug() is sufficient. Additionally log(5, msg) isn't what I want. How can I add a custom loglevel to a Python logger?
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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
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If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its type, the behavior is undefined. [ Note: most existing implementations of C++
ignore integer overflows. Treatment of division by zero, forming a remainde...
Byte order mark screws up file reading in Java
...va. Some of the files may have a byte order mark in the beginning, but not all. When present, the byte order gets read along with the rest of the first line, thus causing problems with string compares.
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Evaluating a mathematical expression in a string
...p://pyparsing.wikispaces.com/message/view/home/15549426
'''
__note__ = '''
All I've done is rewrap Paul McGuire's fourFn.py as a class, so I can use it
more easily in other places.
'''
class NumericStringParser(object):
'''
Most of this code comes from the fourFn.py pyparsing example
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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
Setting environment variables via launchd.conf no longer works in OS X Yosemite/El Capitan/macOS Sie
...iables will not be set (so you'll need to set them in ~/.bash_profile). Finally, this doesn't seem to work for PATH on El Capitan and Sierra. That needs to be set via 'launchctl config user path ...' and in /etc/paths.
share...