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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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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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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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Configure IIS Express for external access to VS2010 project
I am developing a project in VS2010 and am able to view my site locally via IIS Express. I would like to enable external access over the network.
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SET versus SELECT when assigning variables?
...ed then SET will assign NULL, where SELECT will not make the assignment at all (so the variable will not be changed from its previous value)
As far as speed differences - there are no direct differences between SET and SELECT. However SELECT's ability to make multiple assignments in one shot does ...
How to check if DST (Daylight Saving Time) is in effect, and if so, the offset?
...et returns positive numbers of minutes for zones west of UTC, which are usually stated as negative hours (since they're "behind" UTC). For example, Los Angeles is UTC–8h Standard, UTC-7h DST. getTimezoneOffset returns 480 (positive 480 minutes) in December (winter, Standard Time), rather than -480...
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...
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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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...
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...