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Are list-comprehensions and functional functions faster than “for loops”?
...ike map() , filter() and reduce() faster than a for loop? Why, technically, they run in a C speed , while the for loop runs in the python virtual machine speed ?.
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How to resize superview to fit all subviews with autolayout?
...n a UITableViewCell (to determine row height for example) then you should call it against your cell contentView and grab the height.
Further considerations exist if you have one or more UILabel's in your view that are multiline. For these it is imperitive that the preferredMaxLayoutWidth propert...
How do I partially update an object in MongoDB so the new object will overlay / merge with the exist
...n would be that you are happy with $set, but do not want to explicitly set all fields. How would you pass in the data then?
You know you can do the following:
db.collection.update( { _id:...} , { $set: someObjectWithNewData }
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How to access and test an internal (non-exports) function in a node.js module?
... This should absolutely be the top answer. It does not require rewriting all existing modules with NODE_ENV specific exports, nor does it involve reading in the module as text.
– Adam Yost
Jul 22 '15 at 16:00
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How can I use UUIDs in SQLAlchemy?
... dialect supports UUID columns. This is easy (and the question is specifically postgres) -- I don't understand why the other answers are all so complicated.
Here is an example:
from sqlalchemy.dialects.postgresql import UUID
from flask_sqlalchemy import SQLAlchemy
import uuid
db = SQLAlchemy()
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List all sequences in a Postgres db 8.1 with SQL
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The following query gives names of all sequences.
SELECT c.relname FROM pg_class c WHERE c.relkind = 'S';
Typically a sequence is named as ${table}_id_seq. Simple regex pattern matching will give you the table name.
To get last value of a sequence use the ...
Elegant setup of Python logging in Django
...nowhere else. You can either use a configuration file or do it programmatically step-by-step - it just depends on your requirements. The key thing is that I usually add the handlers I want to the root logger, using levels and sometimes logging.Filters to get the events I want to the appropriate file...
Can you add new statements to Python's syntax?
... a hands-on approach here: I'm going to add an until statement to Python.
All the coding for this article was done against the cutting-edge Py3k branch in the Python Mercurial repository mirror.
The until statement
Some languages, like Ruby, have an until statement, which is the complement to whi...
Calculating frames per second in a game
... mean the value of time that you calculated for the last frame. This way, all previous frames will be included, with the most recent frames weighted the most heavily.
– j_random_hacker
May 23 '13 at 20:37
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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...