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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...
How to check version of python modules?
I just installed the python modules: construct and statlib with setuptools like this:
25 Answers
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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...
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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If table exists drop table then create it, if it does not exist just create it
...s case than not to cover, see locking note below).
Second RENAME ... atomically replaces table definition, refer to
MySQL manual
for details.
At last, DROP ... just cleans up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK...
List all sequences in a Postgres db 8.1 with SQL
...
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 ...
Unioning two tables with different number of columns
... I realized that this solution also works without having to list all the columns. So instead of Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2, one can also do, Select *, Null as Col4, Null as Col5 from Table2.
– Pratik Patel
Sep 20 '...
How to measure time in milliseconds using ANSI C?
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Doesn't this measure cpu time and not wall time?
– krs013
Feb 1 '15 at 4:53
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Structure padding and packing
....
A note though - unaligned memory access is slower on architectures that allow it (like x86 and amd64), and is explicitly prohibited on strict alignment architectures like SPARC.
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What is the difference between exit and return? [duplicate]
...hat is difference between return and exit statement in C programming when called from anywhere in a C program?
4 Answers
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