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Difference between Python's Generators and Iterators
..., but not vice versa. A generator is built by calling a function that has one or more yield expressions (yield statements, in Python 2.5 and earlier), and is an object that meets the previous paragraph's definition of an iterator.
You may want to use a custom iterator, rather than a generator, when...
Inserting multiple rows in a single SQL query? [duplicate]
...
And please note that the maximum number of rows in one insert statement is 1000.
– cryss
Mar 21 '13 at 13:39
188
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How to remove a key from a Python dictionary?
... dictionary, use the two-argument form of dict.pop():
my_dict.pop('key', None)
This will return my_dict[key] if key exists in the dictionary, and None otherwise. If the second parameter is not specified (ie. my_dict.pop('key')) and key does not exist, a KeyError is raised.
To delete a key that i...
How should I log while using multiprocessing in Python?
...l log entries should be timestamped.
Your controller process can then do one of the following:
If using disk files: Coalesce the log files at the end of the run, sorted by timestamp
If using pipes (recommended): Coalesce log entries on-the-fly from all pipes, into a central log file. (E.g., Peri...
Initialization of all elements of an array to one default value in C++?
...a single call to fill_nto fill an entire 2D array. You need to loop across one dimension, while filling in the other.
– Evan Teran
Oct 3 '13 at 14:38
8
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Measure the time it takes to execute a t-sql query
...queries using SqlServer 2005. How can I measure how long it takes for each one to run?
6 Answers
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jQuery Validate Required Select
...alue of the id attribute. This is a bit confusing since when working in JS one usually works with the id and not the name. See documentation here: "rules (default: rules are read from markup (classes, attributes, data)) Type: Object Key/value pairs defining custom rules. Key is the name of an elemen...
VIM Replace word with contents of paste buffer?
..., not an EX command such as :%s///g . I know that this is the typical way one replaces the word at the current cursor position: cw<text><esc> but is there a way to do this with the contents of the unnamed register as the replacement text and without overwriting the register?
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Why does Python use 'magic methods'?
I've been playing around with Python recently, and one thing I'm finding a bit odd is the extensive use of 'magic methods', e.g. to make its length available, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
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Is there a decorator to simply cache function return values?
...mple of an LRU cache for computing Fibonacci numbers:
@lru_cache(maxsize=None)
def fib(n):
if n < 2:
return n
return fib(n-1) + fib(n-2)
>>> print([fib(n) for n in range(16)])
[0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610]
>>> print(fib.cache_in...