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Approximate cost to access various caches and main memory?
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@Dave that's true, but this numbers show the order of magnitude
– Andrey
Nov 3 '10 at 13:24
8
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Using GCC to produce readable assembly?
...hem. In this case, one is overriding the other, probably depending on the order in which they're used.
– Adam Rosenfield
Aug 17 '09 at 19:28
4
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java.util.regex - importance of Pattern.compile()?
...d reset a Matcher object that is only ever used by one thread at a time in order to reduce allocations.
– AndrewF
Jul 3 '19 at 20:40
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How to filter array in subdocument with MongoDB [duplicate]
...ents that match the
condition. The returned elements are in the original order.
db.test.aggregate([
{$match: {"list.a": {$gt:3}}}, // <-- match only the document which have a matching element
{$project: {
list: {$filter: {
input: "$list",
as: "list",
...
JavaScript and Threads
...me parameters by the URL and the iframe can communicate with his parent in order to get the result and print it back (the iframe must be in the same domain).
This example doesn't work in all browsers! iframes usually run in the same thread/process as the main page (but Firefox and Chromium seem to ...
Is there a better alternative than this to 'switch on type'?
...17 switching on types is supported - see Zachary Yates's answer below). In order to do this without a large if/else if/else statement, you'll need to work with a different structure. I wrote a blog post awhile back detailing how to build a TypeSwitch structure.
https://docs.microsoft.com/archive/bl...
How does BLAS get such extreme performance?
...itten for one matrix already being transposed. That's why it's "only" one order of magnitude slower than BLAS! But yeah, it's still thrashing because of the lack of cache-blocking. Are you sure Fortran would help much? I think all you'd gain here is that restrict (no aliasing) is the default, un...
How to measure time in milliseconds using ANSI C?
...ng that timeval::tv_usec is always under one second, it's looping. I.e. in order to take differences of time larger than 1 sec, you should: long usec_diff = (e.tv_sec - s.tv_sec)*1000000 + (e.tv_usec - s.tv_usec);
– Alexander Malakhov
Oct 15 '12 at 4:06
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Use git “log” command in another folder
I have some php files in a Folder A (which is a git project). In these php file I want to execute "git log" but for the folder B. Folder B is another git project (so log is different between A and B).
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How to generate all permutations of a list?
... and above ONLY
First, import itertools:
import itertools
Permutation (order matters):
print list(itertools.permutations([1,2,3,4], 2))
[(1, 2), (1, 3), (1, 4),
(2, 1), (2, 3), (2, 4),
(3, 1), (3, 2), (3, 4),
(4, 1), (4, 2), (4, 3)]
Combination (order does NOT matter):
print list(itertools.c...