Cython function:
@cython.boundscheck(False)
@cython.wraparound(False)
def minmaxAvg(list x):
cdef int i
cdef int _min, _max, total
_min = x[0]
_max = x[0]
total = 0
for i in x:
if i < _min: _min = i
elif i > _max: _max = i
total += i
return _min, _max, total/len(x)
pure python function to compare against:
def builtinfuncs(x):
a = min(x)
b = max(x)
avg = sum(x) / len(x)
return a,b,avg
In [16]: x = [random.randint(0,1000) for _ in range(10000)]
In [17]: %timeit minmaxAvg(x)
10000 loops, best of 3: 34 µs per loop
In [18]: %timeit frob(x)
1000 loops, best of 3: 460 µs per loop
Disclaimer:
- Speed result from cython will be dependent on computer hardware.
- Not as flexible and foolproof as using builtins. You would have to change the function to handle anything but integers for example.
- Before going down this path, you should ask yourself if this operation really is a big bottleneck in your application. It's probably not.