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jQuery Validate Required Select
...alue of the id attribute. This is a bit confusing since when working in JS one usually works with the id and not the name. See documentation here: "rules (default: rules are read from markup (classes, attributes, data)) Type: Object Key/value pairs defining custom rules. Key is the name of an elemen...
MySQL Error 1215: Cannot add foreign key constraint
...ing to use as a foreign key are primary keys in their own tables. I have done both of these things, if I'm not mistaken. Any other help you guys could offer?
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Why does Python use 'magic methods'?
I've been playing around with Python recently, and one thing I'm finding a bit odd is the extensive use of 'magic methods', e.g. to make its length available, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
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How to add texture to fill colors in ggplot2
...s to fill colors. Is there an official ggplot2 way to do this or does anyone have a hack that they use? By textures I mean things like diagonal bars, reverse diagonal bars, dot patterns, etc that would differentiate fill colors when printed in black and white.
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VIM Replace word with contents of paste buffer?
..., not an EX command such as :%s///g . I know that this is the typical way one replaces the word at the current cursor position: cw<text><esc> but is there a way to do this with the contents of the unnamed register as the replacement text and without overwriting the register?
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Is there a decorator to simply cache function return values?
...mple of an LRU cache for computing Fibonacci numbers:
@lru_cache(maxsize=None)
def fib(n):
if n < 2:
return n
return fib(n-1) + fib(n-2)
>>> print([fib(n) for n in range(16)])
[0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610]
>>> print(fib.cache_in...
Understanding the Event Loop
...es of stuff that needs doing and every "tick" of the event loop it selects one, removes it from the queue, and runs it.
A key thing to understand is that node relies on the OS for most of the heavy lifting. So incoming network requests are actually tracked by the OS itself and when node is ready to...
Comparing two NumPy arrays for equality, element-wise
...ge behavior in a particular case: if either A or B is empty and the other one contains a single element, then it return True. For some reason, the comparison A==B returns an empty array, for which the all operator returns True.
Another risk is if A and B don't have the same shape and aren't broadca...
PHP convert XML to JSON
...to json in php. If I do a simple convert using simple xml and json_encode none of the attributes in the xml show.
19 Answer...
How to write lists inside a markdown table?
Can one create a list (bullets, numbered or not) inside a markdown table.
6 Answers
6
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