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What would cause an algorithm to have O(log n) complexity?
...r of steps will be logarithmic.
So where does this come up? One classic example is binary search, a fast algorithm for searching a sorted array for a value. The algorithm works like this:
If the array is empty, return that the element isn't present in the array.
Otherwise:
Look at the middle ...
Migrating from JSF 1.2 to JSF 2.0
...echnology which you are currently using and which you want to use.
JSP 2.x to JSP 2.x = Almost no effort.
Facelets 1.x to Facelets 2.0 = Little effort.
JSP 2.x to Facelets 2.0 = Lot of effort. Double this if you also have custom components.
Basic changes
Regardless of the view technology swit...
How do you diff a directory for only files of a specific type?
...
You can specify -x more than once.
diff -x '*.foo' -x '*.bar' -x '*.baz' /destination/dir/1 /destination/dir/2
From the Comparing Directories section of info diff (on my system, I have to do info -f /usr/share/info/diff.info.gz):
To ig...
hexadecimal string to byte array in python
I have a long Hex string that represents a series of values of different types. I wish to convert this Hex String into a byte array so that I can shift each value out and convert it into its proper data type.
...
How to convert an int to a hex string?
...
You are looking for the chr function.
You seem to be mixing decimal representations of integers and hex representations of integers, so it's not entirely clear what you need. Based on the description you gave, I think one of these snippets shows what you want.
>>> chr(0...
Converting a list to a set changes element order
...> a = [1, 2, 20, 6, 210]
>>> b = set([6, 20, 1])
>>> [x for x in a if x not in b]
[2, 210]
If you need a data structure that supports both fast membership tests and preservation of insertion order, you can use the keys of a Python dictionary, which starting from Python 3.7 is ...
How exactly does the python any() function work?
...st) would be False. If lst also contained any of the following [-1, True, "X", 0.00001] (all of which evaluate to True) then any(lst) would be True.
In the code you posted, x > 0 for x in lst, this is a different kind of iterable, called a generator expression. Before generator expressions were ...
Changing the “tick frequency” on x or y axis in matplotlib?
I am trying to fix how python plots my data.
11 Answers
11
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Draw a perfect circle from user's touch
... on the screen as they touch with their fingers. Very simple App I did as exercise way back.
My little cousin took the liberty of drawing things with his finger with my iPad on this App (Kids drawings: circle, lines, etc, whatever came to his mind).
Then he started to draw circles and then he asked ...
Python list subtraction operation
...
Use a list comprehension:
[item for item in x if item not in y]
If you want to use the - infix syntax, you can just do:
class MyList(list):
def __init__(self, *args):
super(MyList, self).__init__(args)
def __sub__(self, other):
return self._...