sum list is faster or fomula?!

Question

i got diffrenet results with change x value sometimes formula is faster or sum list in loop!
https://code.sololearn.com/cqFuj68UGhNn/?ref=app

Answer 1

mohammed shibli ,
to get something like reliable values for the execution time of doing a summation, the code should be modify:

x = 11 # this is to less steps that has to be done. in this case we get a very wide spread of resulting time. should be at least 1_000_000
print(ad[0])
st1 = time.process_time_ns() # the measure unit is to small, so we get large numbers to compare
for i in range(1, x+1):
res1 = (i*(i+1)//2)
#txt1 = f'({i} * ({i} + 1) // 2)' # remove everything that is not directly related to the summation process
#print(res1, txt1) # remove everything that is not directly related to the summation process

Answer 2

mohammed shibli ,

in the file you can find a sample of how it can be done.

https://code.sololearn.com/ccJ0KSEihfzM/?ref=app

Answer 3

Also consider effects of warming up the interpreter and just in time compilation. Using a huge number of tests will help, but a warm-up phase should be used before starting any measurements. And if you want to interpret the results, include a five stats evaluation (min, max, median, and 1/4 and 3/4 quantils), and the average and standard deviation.

Answer 4

thank you Lothar for pointing it out, i try to update it but you nealed it faster.
for time func that's correct timeit is better than process_time_ns
and using many prints just to clear my point

is this faster
>>> (11*(11+1)//2)
or this one:
>>> sum([x for x in range(11+1)])