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Is there a NumPy function to return the first index of something in an array?
...:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so woul...
Skip certain tables with mysqldump
...table=schema.table2 > db-data.sql
The resulting two files are structurally sound but the dumped data is now ~500MB rather than 9GB, much better for me. I can now import these two files into another database for testing purposes without having to worry about manipulating 9GB of data or running o...
How to replace spaces in file names using a bash script
...whole question is about micro-optimizing more or less. Isn't it fun, after all? ;-)
– Michael Krelin - hacker
Apr 26 '10 at 18:33
17
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Create an empty list in python with certain size
...st comprehension (Using the squares because for range you don't need to do all this, you can just return range(0,9) ):
>>> def display():
... return [x**2 for x in range(9)]
...
>>> print display()
[0, 1, 4, 9, 16, 25, 36, 49, 64]
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Is there a way for multiple processes to share a listening socket?
...POSIX type OS), using fork() will cause the forked child to have copies of all the parent's file descriptors. Any that it does not close will continue to be shared, and (for example with a TCP listening socket) can be used to accept() new sockets for clients. This is how many servers, including Apac...
Resetting generator object in Python
I have a generator object returned by multiple yield. Preparation to call this generator is rather time-consuming operation. That is why I want to reuse the generator several times.
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Python argparse mutual exclusive group
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add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
p...
How do I create a multiline Python string with inline variables?
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This isn't really the same because the OP wants named parameters, not positional ones.
– Ismail Badawi
Apr 11 '12 at 19:33
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What is a regular expression for a MAC Address?
...at" comes from Wikipedia, not the 802.3 standards body. IEEE 802-2014 actually specifies hyphens for ordinary MAC addresses (§ 8.1 ¶ 3) and colons for the obsolescent bit-reversed notation (¶ 4). Importantly, in practice, no one observes this. We simply use one or the other, but never mix them...
Immutable vs Mutable types
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Almost, but not exactly. Technically, all variables are passed by reference in Python, but have a semantics more like pass by value in C. A counterexample to your analogy is if you do def f(my_list): my_list = [1, 2, 3]. With pass-by-reference in C, the val...