On 16/04/2017 16:00, justin walters wrote:
On Sun, Apr 16, 2017 at 3:55 AM, bartc <b...@freeuk.com> wrote:
Example C of the same silly program in Python:
def add(a,b):
return a+b
def testfn():
sum=a=b=0
for i in range(100000000):
sum += add(a,b)
a += 1
b += 2
print (a,b,sum)
testfn()
Timings:
A (Pure HLL**) 13 seconds (dynamic/interpreted)
A (With ASM module) 3
B (my compiler) 0.5 (static/compiled)
C (Python 2/xrange) 30
C (Python 3) 38
C (Pypy) 5
Just for fun I wanted to write this up in Nim to compare execution time.
Nim has Python-esqe syntax but is statically
(Nice-looking language, I hadn't heard of it.)
typed and compiled. I think this is relevant to the discussion.
Code looks like this:
```
import times
proc add(a, b: int): int =
result = a + b
proc test() =
var
sum = 0
a = 0
b = 0
for i in 0..<100000000:
Loop iterations should be 100 million, if this is one less. Missing one
out won't affect the timing, but will give a different result if
comparing implementations to see if they do the same thing.
With 100M, the results are (of a,b and sum):
100000000 200000000 14999999850000000
sum += add(a, b)
a += 1
b += 1
b += 2, both to the ensure the same output, and in case there's a sneaky
optimisation it can do for b+=1...
echo "a: " & $a & " b: " & $b & "\n"
echo "Sum: " & $sum
when isMainModule:
var t0 = cpuTime()
test()
var t1 = cpuTime()
echo "***Execution Time: " & $(t1 - t0) & "***\n"
```
No optimization: ***Execution Time: 2.876923***
Optimized for speed: ***Execution Time: 2.844163***
Optimized for size: ***Execution Time: 2.844901***
Hmm, the optimiser is similar to mine then!
Release option: ***Execution Time: 2.844021***
So, generally around 2.8 seconds.
Not too bad for a GC'd language. There are probably some more optimizations
I could make to improve execution time.
What were the results with Python on your machine?
--
bartc
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