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C dynamically growing array
...ynamic array implementations work by starting off with an array of some (small) default size, then whenever you run out of space when adding a new element, double the size of the array. As you can see in the example below, it's not very difficult at all: (I've omitted safety checks for brevity)
type...
Pandas percentage of total with groupby
... is a table of some kind, so 100 * x doesn't intuitively make sense (especially when some of the cells contain strings like AZ, ...).
– dhardy
Feb 6 '15 at 9:42
6
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Hidden features of Perl?
What are some really useful but esoteric language features in Perl that you've actually been able to employ to do useful work?
...
Is there a decorator to simply cache function return values?
...maxsize=100, typed=False)
Decorator to wrap a function with a memoizing callable that saves up to the maxsize most recent calls. It can save time when an expensive or I/O bound function is periodically called with the same arguments.
Example of an LRU cache for computing Fibonacci numbers:
@lru...
Using numpy to build an array of all combinations of two arrays
...
It should be noted that meshgrid only works for smaller range sets, I have a large one and I get error: ValueError: maximum supported dimension for an ndarray is 32, found 69
– mikkom
Oct 20 '19 at 6:54
...
PHP $_SERVER['HTTP_HOST'] vs. $_SERVER['SERVER_NAME'], am I understanding the man pages correctly?
...you either go with that or you check the host name against a white list:
$allowed_hosts = array('foo.example.com', 'bar.example.com');
if (!isset($_SERVER['HTTP_HOST']) || !in_array($_SERVER['HTTP_HOST'], $allowed_hosts)) {
header($_SERVER['SERVER_PROTOCOL'].' 400 Bad Request');
exit;
}
...
How do I profile memory usage in Python?
...
This one has been answered already here: Python memory profiler
Basically you do something like that (cited from Guppy-PE):
>>> from guppy import hpy; h=hpy()
>>> h.heap()
Partition of a set of 48477 objects. Total size = 3265516 bytes.
Index Count % Size % Cumulat...
A complete solution to LOCALLY validate an in-app receipts and bundle receipts on iOS 7
...receipt success:successBlock failure:nil]; // failureBlock is nil intentionally. See below.
if (verified) return;
// Apple recommends to refresh the receipt if validation fails on iOS
[[RMStore defaultStore] refreshReceiptOnSuccess:^{
RMAppReceipt *receipt = [RMAppReceipt bundleReceipt];
[s...
Are PHP Variables passed by value or by reference?
... function is changed, it does not get changed outside of the function). To allow a function to modify its arguments, they must be passed by reference.
To have an argument to a function always passed by reference, prepend an ampersand (&) to the argument name in the function definition.
&l...
Progress indicator during pandas operations
...se you're interested in how this works (and how to modify it for your own callbacks), see the examples on github, the full documentation on pypi, or import the module and run help(tqdm). Other supported functions include map, applymap, aggregate, and transform.
EDIT
To directly answer the original ...