Re: Baby X is bor nagain

On 20/06/2024 21:16, David Brown wrote:

On 20/06/2024 18:58, bart wrote:

No, the complaint was getting it so wrong in the first place, then taking too long to fix it. (I think it was in Python 3 that you could type 'range' instead of 'xrange'.)
>
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 s = 0
for i in range(10000000) :
     s = s + i
print(s)
  (I made it 10 million, not 1 million, because I have such a vastly faster computer than everyone else.)
 $ time python2 sum.py
49999995000000
 real    0m0,820s
user    0m0,632s
sys    0m0,179s
 $ time python3 sum.py
49999995000000
 real    0m0,868s
user    0m0,854s
sys    0m0,004s

During the last 20 or more years, Python implementations have gotten more and more efficient. So if there is a difference between range and xrange, there are techniques that can be used to minimise it.
But if should never have been done that crazy way in the first place.
However if I compare range to xrange now on Py2 using such loops as your examples, then xrange is about twice as fast. But range on Py3 is in-between. Basically I've no idea what's going on inside it these days.
(You should run the loop in your example inside a function, which makes it twice as fast. CPython on my Windows machine runs it in 0.6 seconds.
My language can do it in 0.5 seconds, but that's for a 100M loop.)