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sys.argv[1] meaning in script
...more tutorial level.
For every invocation of Python, sys.argv is automatically a list of strings representing the arguments (as separated by spaces) on the command-line. The name comes from the C programming convention in which argv and argc represent the command line arguments.
You'll want to lea...
How can I export tables to Excel from a webpage [closed]
... can I export tables to Excel from a webpage. I want the export to contain all the formatting and colours.
14 Answers
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Difference between numpy.array shape (R, 1) and (R,)
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1. The meaning of shapes in NumPy
You write, "I know literally it's list of numbers and list of lists where all list contains only a number" but that's a bit of an unhelpful way to think about it.
The best way to think about NumPy arrays is that they consist of two parts, a data bu...
What is the use of “assert” in Python?
...t True # nothing happens
>>> assert False
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
Assertions can include an optional message, and you can disable them when running the interpreter.
To print a message if the assertion fails:
ass...
Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_
...AMD documents it and compilers don't expose it.)
(Yes, these instructions all run on the same execution unit).
This dependency doesn't just hold up the 4 popcnts from a single loop iteration. It can carry across loop iterations making it impossible for the processor to parallelize different loop...
Is [UIScreen mainScreen].bounds.size becoming orientation-dependent in iOS8?
...would be even more helpful if it was explained what interface oriented actually means. I may be wrong, but I think the orientation dependence only pertains to view controllers. If you take any other class and calculate the bounds, they are still according to the old style, always portrait.
...
What is function overloading and overriding in php?
...that method.
In PHP, you can only overload methods using the magic method __call.
An example of overriding:
<?php
class Foo {
function myFoo() {
return "Foo";
}
}
class Bar extends Foo {
function myFoo() {
return "Bar";
}
}
$foo = new Foo;
$bar = new Bar;
echo($foo-&...
How to prevent IFRAME from redirecting top-level window
...
iFrames do allow cross-domain communication, though, using postMessage. This isn't a security risk, but someone might care to know that this capability exists when they see your comment. :)
– coreyward
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Conditions for automatic generation of default/copy/move ctor and copy/move assignment operator?
I want to refresh my memory on the conditions under which a compiler typically auto generates a default constructor, copy constructor and assignment operator.
...
What is the standard naming convention for html/css ids and classes?
...
There isn't one.
I use underscores all the time, due to hyphens messing up the syntax highlighting of my text editor (Gedit), but that's personal preference.
I've seen all these conventions used all over the place. Use the one that you think is best - the one...