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How is Python's List Implemented?
...the same time regardless of index:
...>python -m timeit --setup="x = [None]*1000" "x[500]"
10000000 loops, best of 3: 0.0579 usec per loop
...>python -m timeit --setup="x = [None]*1000" "x[0]"
10000000 loops, best of 3: 0.0566 usec per loop
I would be astounded if IronPython or Jython used...
Difference between Arrays.asList(array) and new ArrayList(Arrays.asList(array))
...ou create new ArrayList, which is a full, independent copy of the original one. Although here you create the wrapper using Arrays.asList as well, it is used only during the construction of the new ArrayList and is garbage-collected afterwards. The structure of this new ArrayList is completely indepe...
How to change MySQL data directory?
...ed to solve the problem for me on Ubuntu 12.04 (Precise). I found out that one needs to edit the file /etc/apparmor.d/tunables/alias to include a line "alias /var/lib/mysql/ -> /newpath/," With this in place, I did not need any changes in any of the other AppArmor files. It worked immediately aft...
Diff output from two programs without temporary files
...
Use <(command) to pass one command's output to another program as if it were a file name. Bash pipes the program's output to a pipe and passes a file name like /dev/fd/63 to the outer command.
diff <(./a) <(./b)
Similarly you can use >(...
What does O(log n) mean exactly?
... that:
the choice of the next element on which to perform some action is one of several possibilities, and
only one will need to be chosen.
or
the elements on which the action is performed are digits of n
This is why, for example, looking up people in a phone book is O(log n). You don't need...
How to check if all list items have the same value and return it, or return an “otherValue” if they
...val) ? val : otherValue;
Cleanest way I can think of. You can make it a one-liner by inlining val, but First() would be evaluated n times, doubling execution time.
To incorporate the "empty set" behavior specified in the comments, you simply add one more line before the two above:
if(yyy == nu...
Purpose of Unions in C and C++
...g of the rooms (i.e. by making sure different people don't get assigned to one room at the same time), a relatively small hotel can provide accommodations to a relatively large number of people, which is what hotels are for.
That's exactly what union does. If you know that several objects in your p...
ggplot with 2 y axes on each side and different scales
...ed to plot a bar chart showing counts and a line chart showing rate all in one chart, I can do both of them separately, but when I put them together, I scale of the first layer (i.e. the geom_bar ) is overlapped by the second layer (i.e. the geom_line ).
...
FileSystemWatcher vs polling to watch for file changes
...chines in the field. We had problems with both local dir and file share. One of the probable causes we came up with was the copy/creation of a lot of files in a short amount of time in the directory.
– Jason Jackson
Oct 27 '08 at 17:26
...
How do I use method overloading in Python?
... method overloading not method overriding. And in Python, you do it all in one function:
class A:
def stackoverflow(self, i='some_default_value'):
print 'only method'
ob=A()
ob.stackoverflow(2)
ob.stackoverflow()
You can't have two methods with the same name in Python -- and you...