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Dictionary vs Object - which is more efficient and why?

...ots__ = ('i', 'l') def __init__(self, i): self.i = i self.l = [] all = {} for i in range(1000000): all[i] = Obj(i) test_obj.py: class Obj(object): def __init__(self, i): self.i = i self.l = [] all = {} for i in range(1000000): all[i] = Obj(i) test_dict.py: all = {} for i in...
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Reverse a string in Python

... @Tanner [::-1] is fastest because it does not call any external functions, rather it's using slicing, which is highly-optimized in python. ''.join(list(reversed(s))) makes 3 function calls. – hd1 Apr 27 at 13:51 ...
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How do I do a not equal in Django queryset filtering?

... Your query appears to have a double negative, you want to exclude all rows where x is not 5, so in other words you want to include all rows where x IS 5. I believe this will do the trick. results = Model.objects.filter(x=5).exclude(a=true) To answer your specific question, there is no "...
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Unzip a file with php

...e it out by yourself. On the other hand, the fact that this code could actually be published online somewhere as the correct way to unzip a file is a bit frightening. PHP has built-in extensions for dealing with compressed files. There should be no need to use system calls for this. ZipArchivedocs ...
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(-2147483648> 0) returns true in C++?

-2147483648 is the smallest integer for integer type with 32 bits, but it seems that it will overflow in the if(...) sentence: ...
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How to find the mysql data directory from command line in windows

In linux I could find the mysql installation directory with the command which mysql . But I could not find any in windows. I tried echo %path% and it resulted many paths along with path to mysql bin. ...
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Python set to list

...k that you didn't overwrite list by accident: >>> assert list == __builtins__.list share | improve this answer | follow | ...
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Checking if array is multidimensional or not?

...will recursively count the array. This is particularly useful for counting all the elements of a multidimensional array. count() does not detect infinite recursion. However this method does not detect array(array()). share...
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Random row selection in Pandas dataframe

... Thanks @eumiro. I also worked out that df.ix[np.random.random_integers(0, len(df), 10)] would also work. – John Apr 10 '13 at 10:58 7 ...
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Is there an alternative sleep function in C to milliseconds?

...s defined usleep(), so this is available on Linux: int usleep(useconds_t usec); DESCRIPTION The usleep() function suspends execution of the calling thread for (at least) usec microseconds. The sleep may be lengthened slightly by any system activity or by the tim...