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How to sort a list of objects based on an attribute of the objects?
...is a need to sort by multiple fields, it could be achieved by consecutive calls to sort(), because python is using stable sort algorithm.
– zzz777
Feb 23 at 14:41
add a commen...
How to get name of exception that was caught in Python?
...n't want to catch particular exceptions known in advance. I want to catch all exceptions.
– Rob Bednark
Apr 27 '18 at 16:10
add a comment
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Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...t is both commutative and associative. This means the operation can be parallelized.
This distinction is very important for Big Data / MPP / distributed computing, and the entire reason why reduce even exists. The collection can be chopped up and the reduce can operate on each chunk, then the red...
How can I find script's directory with Python? [duplicate]
...
You need to call os.path.realpath on __file__, so that when __file__ is a filename without the path you still get the dir path:
import os
print(os.path.dirname(os.path.realpath(__file__)))
...
SQL SELECT WHERE field contains words
...%'
OR column1 LIKE '%word2%'
OR column1 LIKE '%word3%'
If you need all words to be present, use this:
SELECT * FROM mytable
WHERE column1 LIKE '%word1%'
AND column1 LIKE '%word2%'
AND column1 LIKE '%word3%'
If you want something faster, you need to look into full text search, and this...
What exactly does Perl's “bless” do?
...to a hash (most common case), to an array (not so common), to a scalar (usually this indicates an inside-out object), to a regular expression, subroutine or TYPEGLOB (see the book Object Oriented Perl: A Comprehensive Guide to Concepts and Programming Techniques by Damian Conway for useful examples)...
Why doesn't Python have a sign function?
... it wasn't accepted, because they didn't agree on what it should return in all the edge cases (+/-0, +/-nan, etc)
So they decided to implement only copysign, which (although more verbose) can be used to delegate to the end user the desired behavior for edge cases - which sometimes might require the...
I want to delete all bin and obj folders to force all projects to rebuild everything
I work with multiple projects, and I want to recursively delete all folders with the name 'bin' or 'obj' that way I am sure that all projects will rebuild everything (sometimes it's the only way to force Visual Studio to forget all about previous builds).
...
Make elasticsearch only return certain fields?
...fields from there. May impact performance if returned data is relatively small to the size of a whole document.
– Zaar Hai
Aug 18 '13 at 10:19
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Python Dictionary Comprehension
...>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple keys at once on an existing dictionary. ...