I’ve seen people say that set objects in python have O(1) membership-checking. How are they implemented internally to allow this? What sort of data structure does it use? What other implications does that implementation have? Every answer here was really enlightening, but I can only accept one, so I’ll go with the closest answer to … Read more
When comparing floats to integers, some pairs of values take much longer to be evaluated than other values of a similar magnitude. For example: >>> import timeit >>> timeit.timeit(“562949953420000.7 < 562949953421000”) # run 1 million times 0.5387085462592742 But if the float or integer is made smaller or larger by a certain amount, the comparison runs … Read more
What’s all this fuss about Python and CPython (Jython,IronPython), I don’t get it: python.org mentions that CPython is: The “traditional” implementation of Python (nicknamed CPython) yet another Stack Overflow question mentions that: CPython is the default byte-code interpreter of Python, which is written in C. Honestly I don’t get what both of those explanations practically … Read more
I’ve been hearing a lot about the PyPy project. They claim it is 6.3 times faster than the CPython interpreter on their site. Whenever we talk about dynamic languages like Python, speed is one of the top issues. To solve this, they say PyPy is 6.3 times faster. The second issue is parallelism, the infamous … Read more
def main(): for i in xrange(10**8): pass main() This piece of code in Python runs in (Note: The timing is done with the time function in BASH in Linux.) real 0m1.841s user 0m1.828s sys 0m0.012s However, if the for loop isn’t placed within a function, for i in xrange(10**8): pass then it runs for a … Read more
