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Are loops really faster in reverse?
I've heard this quite a few times. Are JavaScript loops really faster when counting backward? If so, why? I've seen a few test suite examples showing that reversed loops are quicker, but I can't find any explanation as to why!
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Pairs from single list
...e=2):
it = iter(t)
return izip(*[it]*size)
When you want to pair all elements you obviously might need a fillvalue:
from itertools import izip_longest
def blockwise(t, size=2, fillvalue=None):
it = iter(t)
return izip_longest(*[it]*size, fillvalue=fillvalue)
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LINQ - Left Join, Group By, and Count
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.Count() will generate COUNT(*) which will count all the rows in that group, by the way.
– Mehrdad Afshari
Mar 29 '09 at 22:47
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Why does my application spend 24% of its life doing a null check?
...t store a copy of the bytes in RAM. An important one is the L1 cache, typically 16 kilobytes for data and 16 kilobytes for instructions. Small, allowing it to be close to the execution engine. Reading bytes from the L1 cache typically takes 2 or 3 CPU cycles. Next up is the L2 cache, bigger and slow...
How to find the nearest parent of a Git branch?
...al) are just transient labels that point to specific commits in the continually growing commit DAG. As such, the relationship between branches can vary over time, but the relationship between commits does not.
---o---1 foo
\
2---3---o bar
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MySQL foreign key constraints, cascade delete
...#2 (blue):
DELETE FROM categories WHERE (id = 2);
the DBMS will look at all the tables which have a foreign key pointing at the 'categories' table, and delete the records where the matching id is 2. Since we only defined the foreign key relationship in products_categories, you end up with this ta...
CSS to make HTML page footer stay at bottom of the page with a minimum height, but not overlap the p
...just omit the "height" and the footer will adapt to content. Not tested in all browser
– m47730
Sep 23 '15 at 7:58
Thi...
What XML parser should I use in C++? [closed]
... process XML. Not toy XML, real XML. You need to be able to read and write all of the XML specification, not just the low-lying, easy-to-parse bits. You need Namespaces, DocTypes, entity substitution, the works. The W3C XML Specification, in its entirety.
The next question is: Does your API need to ...
git -> show list of files changed in recent commits in a specific directory
...n. If you need a comprehensive list of commits, try making the number unusually large, like -1000 or more as needed.
– Julian Soro
Jan 8 '15 at 20:07
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Test or check if sheet exists
Basically I loop through all sheets in the origin workbook then set destsheet in the destination workbook to the sheet with the same name as the currently iterated one in the origin workbook.
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