Cython_demo.ipynb

Kernel: Python 2 (SageMath)

Some quick contrived Hello Maths! code examples in Python and Cython to show how Cython can speed up Python code.

iters=1000
n=10000

def pmaxsqrt(n):
    maxsofar = 0.0
    from math import sqrt
    for a in range(n):
        x=sqrt(a)
        if x > maxsofar:
            maxsofar = x
    return maxsofar

def pfun(n,iters):
    import timeit
    nstr=str(n)
    return timeit.timeit('pmaxsqrt('+nstr+')', number=iters, setup='from __main__ import pmaxsqrt')

pfun(n,iters)

1.1704959869384766

%load_ext Cython

%%cython

cpdef cmaxsqrt(n):
    maxsofar = 0.0
    from math import sqrt
    for a in range(n):
        x=sqrt(a)
        if x > maxsofar:
            maxsofar = x
    return maxsofar

def cfun(n,iters):
    import timeit
    nstr=str(n)
    return timeit.timeit('cmaxsqrt('+nstr+')', number=iters, setup='from __main__ import cmaxsqrt')

cfun(n,iters)

0.6352179050445557

%%cython

cpdef tmaxsqrt(int n):
    cdef double x
    cdef double maxsofar = 0.0
    from math import sqrt
    for a in range(n):
        x=sqrt(a)
        if x > maxsofar:
            maxsofar = x
    return maxsofar

def tfun(n,iters):
    import timeit
    nstr=str(n)
    return timeit.timeit('tmaxsqrt('+nstr+')', number=iters, setup='from __main__ import tmaxsqrt')

tfun(n,iters)

0.4050180912017822