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C# vs C - Big performance difference
...rdingly, it must call a CRT function that implements sqrt() and checks the selected floating point options to adjust the result. That's slow.
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Does it make any sense to use inline keyword with templates?
...s, multiple equivalent definitions may be passed to the linker, which will select one). That, not inlining, is the real function of the inline keyword.
– Ben Voigt
Jul 10 '12 at 21:12
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How to generate keyboard events in Python?
... uparrow = 0x26
rightarrow = 0x27
downarrow = 0x28
select = 0x29
print = 0x2A
execute = 0x2B
printscreen = 0x2C
insert = 0x2D
delete = 0x2E
help = 0x2F
num0 = 0x30
num1 = 0x31
num2 = 0x32
num3 = 0...
Multiple aggregations of the same column using pandas GroupBy.agg()
... column names
The values are tuples whose first element is the column to select and the second element is the aggregation to apply to that column.
Pandas provides the pandas.NamedAgg namedtuple with the fields
['column', 'aggfunc'] to make it clearer what the arguments are. As
usual, the agg...
How to change the session timeout in PHP?
..., it was about running 2 additional queries to get these prev/next values. SELECT id FROM gallery WHERE SortOrder > $currentsortorder LIMIT 1
– Your Common Sense
Nov 29 '11 at 13:37
...
Things possible in IntelliJ that aren't possible in Eclipse?
...uctors SimpleTimeZone has.
After Enter in Eclipse
I get the previously selected constructor filled with predefined variable names. And I can see the type of every argument. With Code Recommanders Eclipse guesses the right constructor by the previously defined variable types in the current scope ...
Why should hash functions use a prime number modulus?
...er of buckets. This is convenient and saves having to search around or pre-select a prime number of the right magnitude. So you rely on the hash function not to use even multipliers, which is generally a safe assumption. But you can still get occasional bad hashing behaviours based on hash functions...
Truly understanding the difference between procedural and functional
...ow it will happen - this is powerful because if we can clearly state what "Select" and "Where" and "Aggregate" means, we are free to swap out their implementations, just like we do with AsParallel() and suddenly our single-threaded app scales out to n cores.
...
Maximum single-sell profit
...nd the largest sum of a contiguous subset of that list.
You can trivially convert this problem to that problem by taking the profit or loss between consecutive days. So you would transform a list of stock prices, e.g. [5, 6, 7, 4, 2] into a list of gains/losses, e.g., [1, 1, -3, -2]. The subsequenc...
MySQL foreign key constraints, cascade delete
...RITY DEFINER
BEGIN
DELETE FROM
`products`
WHERE
`id` IN (
SELECT `products_id`
FROM `categories_products`
WHERE `categories_id` = category_ID
)
;
DELETE FROM `categories`
WHERE `id` = category_ID;
END
You also need to add the following foreign key constraints...