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How do I get the number of elements in a list?
...objects with a "size" in Python, in particular, have an attribute called ob_size, where the number of elements in the object is cached. So checking the number of objects in a list is very fast.
But if you're checking if list size is zero or not, don't use len - instead, put the list in a boolean co...
Do try/catch blocks hurt performance when exceptions are not thrown?
...TryCatch() cil managed
{
// Code size 32 (0x20)
.maxstack 8
IL_0000: nop
IL_0001: ldstr "SIN(1) = {0} - No Try/Catch"
IL_0006: ldc.r8 1.
IL_000f: call float64 [mscorlib]System.Math::Sin(float64)
IL_0014: box [mscorlib]System.Double
IL_0019: call ...
Python __call__ special method practical example
I know that __call__ method in a class is triggered when the instance of a class is called. However, I have no idea when I can use this special method, because one can simply create a new method and perform the same operation done in __call__ method and instead of calling the instance, you can c...
Using property() on classmethods
...te the property on the metaclass.
>>> class foo(object):
... _var = 5
... class __metaclass__(type): # Python 2 syntax for metaclasses
... pass
... @classmethod
... def getvar(cls):
... return cls._var
... @classmethod
... def setvar(cls, value):
.....
How to find out which package version is loaded in R?
...plish that.
> sessionInfo()
R version 2.15.0 (2012-03-30)
Platform: x86_64-pc-linux-gnu (64-bit)
locale:
[1] LC_CTYPE=en_US.UTF-8 LC_NUMERIC=C LC_TIME=en_US.UTF-8 LC_COLLATE=en_US.UTF-8
[5] LC_MONETARY=en_US.UTF-8 LC_MESSAGES=en_US.UTF-8 LC_PAPER=C ...
Why is early return slower than else?
...e a theory for you.
I tried your code and get the same of results, without_else() is repeatedly slightly slower than with_else():
>>> T(lambda : without_else()).repeat()
[0.42015745017874906, 0.3188967452567226, 0.31984281521812363]
>>> T(lambda : with_else()).repeat()
[0.3600984...
What's a correct and good way to implement __hash__()?
What's a correct and good way to implement __hash__() ?
6 Answers
6
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Pythonic way to find maximum value and its index in a list?
...many options, for example:
import operator
index, value = max(enumerate(my_list), key=operator.itemgetter(1))
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Safe characters for friendly url [closed]
...igits, hyphen, period, underscore, and tilde."
ALPHA DIGIT "-" / "." / "_" / "~"
Note that RFC 3986 lists fewer reserved punctuation marks than the older RFC 2396.
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jQuery: How can i create a simple overlay?
...ouseenter(showPhotoOverlay);
// Create photo overlay elements
var _isPhotoOverlayDisplayed = false;
var _photoId;
var _photoOverlay = $("<div id='photoOverlay'></div>");
var _photoOverlayShareButton = $("<div id='photoOverlayShare'>Share</div>");
// ...