In [1]:

    

%load_ext Cython


    

In [4]:

    

%%cython
def summer1(double[:] mv):
    """Sums its argument's contents."""
    cdef double d, ss=0.0
    for d in mv:
        ss += d
    return ss


    

In [5]:

    

import numpy as np

arr = np.ones((10**6,), dtype=np.double)


    

In [7]:

    

%timeit -n3 -r3 summer1(arr)


    

    




3 loops, best of 3: 199 ms per loop

In [9]:

    

from array import array

ar = array('d', [1]*10**6)


    

In [10]:

    

%timeit -n3 -r3 summer1(ar)


    

    




3 loops, best of 3: 197 ms per loop

In [26]:

    

%%cython
def summer2(double[:] mv):
    """Sums its argument's contents."""
    cdef:
        double ss=0.0
        int i, N
    N = mv.shape[0]
    for i in range(N):
        ss += mv[i]
    return ss


    

In [29]:

    

%timeit -n3 -r3 summer2(arr)


    

    




3 loops, best of 3: 1.04 ms per loop

In [28]:

    

%timeit -n3 -r3 summer2(ar)


    

    




3 loops, best of 3: 1.02 ms per loop

In [73]:

    

%%cython
from cython cimport wraparound, boundscheck

@boundscheck(False)
@wraparound(False)
cpdef double summer3(double[:] mv):
    """Sums its argument's contents."""
    cdef:
        double ss=0.0
        int i, N
    N = mv.shape[0]
    for i in range(N):
        ss += mv[i]
    return ss


    

In [74]:

    

%timeit -n3 -r3 summer3(arr)


    

    




3 loops, best of 3: 1.05 ms per loop

In [75]:

    

%timeit -n3 -r3 arr.sum()


    

    




3 loops, best of 3: 726 µs per loop