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What is the fastest way to get the value of π?
...
The Monte Carlo method, as mentioned, applies some great concepts but it is, clearly, not the fastest, not by a long shot, not by any reasonable measure. Also, it all depends on what kind of accuracy you are looking for. The fastest π I know of is the one ...
Deep copying an NSArray
...ple documentation about deep copies explicitly states:
If you only need a one-level-deep copy:
NSMutableArray *newArray = [[NSMutableArray alloc]
initWithArray:oldArray copyItems:YES];
The above code creates a new array whose members are shallow copies of the members...
What are free monads?
...erm Free Monad pop up every now and then for some time, but everyone just seems to use/discuss them without giving an explanation of what they are. So: what are free monads? (I'd say I'm familiar with monads and the Haskell basics, but have only a very rough knowledge of category theory.)
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CSS: Change image src on img:hover
...moticon_12-128.png" />
</a>
CSS
a img:last-child {
display: none;
}
a:hover img:last-child {
display: block;
}
a:hover img:first-child {
display: none;
}
jsfiddle: https://jsfiddle.net/m4v1onyL/
Note that the images used are of the same dimensions for proper display. Also,...
How to add a new row to an empty numpy array
...ray in advance. Do you think you can do that? Appending should really be a one or two time operation.
– askewchan
Dec 7 '16 at 16:40
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What does asterisk * mean in Python? [duplicate]
...ng to a new
empty dictionary.
Also, see Function Calls.
Assuming that one knows what positional and keyword arguments are, here are some examples:
Example 1:
# Excess keyword argument (python 2) example:
def foo(a, b, c, **args):
print "a = %s" % (a,)
print "b = %s" % (b,)
print "...
Checking a Python module version at runtime
...e file name, pkg_resources might pick up a different version shadowing the one you are actually running because it has higher precedence on your PYTHONPATH or similar.
– tripleee
Feb 12 '14 at 10:58
...
Signal handling with multiple threads in Linux
...e executed. Once it's executed, control will return, assuming you haven't done anything to alter the normal flow (exit etc).
– Alan
Jul 26 '12 at 23:54
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Why exactly is eval evil?
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There are several reasons why one should not use EVAL.
The main reason for beginners is: you don't need it.
Example (assuming Common Lisp):
EVALuate an expression with different operators:
(let ((ops '(+ *)))
(dolist (op ops)
(print (eval (list op 1...
Facebook Like Button - how to disable Comment pop up?
... to hide the comment box after Facebook Like (XFBML version not the iframe one) is as given:
.fb_edge_widget_with_comment span.fb_edge_comment_widget iframe.fb_ltr {
display: none !important;
}
Put the CSS style in any of your CSS file and see the magic, it works :)
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