Editor project - benchmarking member-by-member summing
Recently I introduced classes for VRect, VPoint and VSize, to mirror Qt classes, and replaced all usages of tuples with these classes. Unfortunately, the code became really, really slow. I expected reduced speed, but not so much to compromise refresh. I am aware that my refresh strategy can be improved, but I decided to investigate really how slow the different strategies are. Here is the code
import time
import collections
a=time.time()
b=(2,3)
for i in range(1000000):
c = (1,1)
b = (b[0]+c[0], b[1]+c[1])
print("Tuples "+str(time.time()-a-0.07))
############
class C:
def __init__(self, x,y):
self._pos = (x,y)
def __add__(self, other):
return C(self._pos[0]+other._pos[0], self._pos[1]+other._pos[1])
a=time.time()
b=C(2,3)
for i in range(1000000):
b = b + C(1,1)
print("Class "+str(time.time()-a-0.07))
#####################
T=collections.namedtuple('T',("x", "y"))
a=time.time()
b=T(2,3)
for i in range(1000000):
c = T(1,1)
b = T(b.x+c.x, b.y+c.y)
print("namedtuple "+str(time.time()-a-0.07))
#####################
T=collections.namedtuple('T',("x", "y"))
a=time.time()
b=T(2,3)
for i in range(1000000):
c = T(1,1)
b = T(b[0]+c[0], b[0]+c[0])
print("namedtuple index "+str(time.time()-a-0.07))
The 0.07 seconds is the time for the empty loop. The results are astonishing
$ python3 test.py
Tuples 0.723123960494995
Class 4.2343959140777585
namedtuple 3.7144619750976564
namedtuple index 2.9126908111572267
Working with raw tuples beats every other technique hands down. It’s quite clear now why my code has become so sluggish. I won’t trash the concept, but I will definitely not use the high level classes for internal operations. Unfortunately this has a price in self-documentation: I definitely prefer to use point.x() or instead of point[0]. An obvious mitigating strategy is to use a constant to get point[X_INDEX].