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__proto__ VS. prototype in JavaScript
...x = x;
this.y = y;
}
var myPoint = new Point();
// the following are all true
myPoint.__proto__ == Point.prototype
myPoint.__proto__.__proto__ == Object.prototype
myPoint instanceof Point;
myPoint instanceof Object;
Here Point is a constructor function, it builds an object (data structure) p...
When to use enumerateObjectsUsingBlock vs. for
...
Ultimately, use whichever pattern you want to use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will be as fas...
How to get indices of a sorted array in Python
... you can get the sorted list and indicies by using zip: sorted_items, sorted_inds = zip(*sorted([(i,e) for i,e in enumerate(my_list)], key=itemgetter(1)))
– Charles L.
Nov 30 '15 at 2:58
...
Where does gcc look for C and C++ header files?
...stem header.
If you run gcc in verbose mode on such a source, it will list all the system include locations as it looks for the bogus header.
$ echo "#include <bogus.h>" > t.c; gcc -v t.c; rm t.c
[..]
#include "..." search starts here:
#include <...> search starts here:
/usr/local...
How to use a decimal range() step value?
...y([ 0. , 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9])
If you really want to use a floating-point step value, you can, with numpy.arange.
>>> import numpy as np
>>> np.arange(0.0, 1.0, 0.1)
array([ 0. , 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9])
Floating-p...
In Python, if I return inside a “with” block, will the file still close?
...
@RikPoggi os._exit is sometimes used - it exits the Python process without calling cleanup handlers.
– Acumenus
Oct 8 '16 at 6:25
...
Upgrading PHP in XAMPP for Windows?
...a backup of your htdocs and data folder (subfolder of MySQL folder), reinstall upgraded version and replace those folders.
Note:
In case you have changed config files like PHP (php.ini), Apache (httpd.conf) or any other, please take back up of those files as well and replace them with newly install...
Why does Go have a “goto” statement
... x = x + 1
}
if x == 2 {
return z
}
x = x - 2
p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
return z * p / q
small:
if x == 0 ...
Forced naming of parameters in Python
...(10, forcenamed=20)
10 20
>>> foo(10, 20)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: foo() takes exactly 1 positional argument (2 given)
This can also be combined with **kwargs:
def foo(pos, *, forcenamed, **kwargs):
...
How to maintain aspect ratio using HTML IMG tag
... The size is fixed, the aspect ratio is not, as the question was specifically about any image of any resolution. Including resolutions smaller than 64x64.
– Koenigsberg
Jul 31 '18 at 8:50
...