Python Random vs. Cython C Rand for Dice Rolls

[Cecil Westerhof]

On Sunday  7 Jun 2015 19:23 CEST, Chris Angelico wrote:

> On Mon, Jun 8, 2015 at 3:17 AM, C.D. Reimer <chris at cdreimer.com> wrote:
>> This is the Python script that takes ~197 seconds to complete.
>>
>> import random, time
>>
>> startTime = time.time()
>>
>> f = [0] * 12
>>
>> for i in range(50000000):
>>
>> a = random.randint(1,6)
>>
>> b = random.randint(1,6)
>>
>> f[(a + b) - 1] += 1
>>
>> print "\nTOTAL SPOTS","\tNUMBER OF TIMES\n"
>>
>> for i in range(1,12):
>>
>> print ' ' + str(i + 1), '\t\t ', f[i]
>>
>> print '\n', time.time() - startTime
>
> Before you go any further, can you just try this script, please, and
> see how long it takes to run?
>
> import random, time
> startTime = time.time()
> for i in range(50000000):
> pass
> print '\n', time.time() - startTime
>
> I know, seems a stupid thing to try, right? But you're using Python
> 2, as evidenced by the print statements, and that means that range()
> is constructing a 50M element list. It's entirely possible that
> that's a significant part of your time - allocating all that memory,
> populating it, and then disposing of it at the end (maybe).
>
> Maybe it'll turn out not to be significant, but there's only one way
> to find out.

I tried this in 2 and 3. In 3 it takes 3.13 seconds and 2 7.5 seconds.
A significant difference, but not in the whole of what he was trying
to do I think.

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof