quetion about "+=" and "runtime"

[gagaguy@gmail.com]

1.i saw "+=" in a program code,but i haven't see it before,neither can
i find it in a cook,who can tell me the usage of "python0"

2.how can i know how long does a program run?

[Terry Reedy]

Re: quetion about "+=&quo t; and "runtime&q uot;


<gagaguy@gmail. com> wrote in message
news:1123123359 .768132.112990@ g47g2000cwa.goo glegroups.com.. .[color=blue]
> 1.i saw "+=" in a program code,but i haven't see it before,neither can
> i find it in a cook,who can tell me the usage of "python0"[/color]

It probably is in the tutorial and certainly is in the reference manual.
I don't understand "usage of 'python0'".
[color=blue]
> 2.how can i know how long does a program run?[/color]

time module

tjr

[gagaguy@gmail.com]

Re: quetion about &quot;+=&quo t; and &quot;runtime&q uot;

1.i have look " += " up,but i can't find it.is it ofthen used?
2.i saq a result like this in a web page:


$ time python permute2.py 56789 3
Got 120 items.
Maximum at 87596 ,product 84000

real 0m0.057s
user 0m0.050s
sys 0m0.000s

$ time python permute3.py 56789 3
Got 120 items.
Maximum at 87596 ,product 84000

real 0m0.040s
user 0m0.030s
sys 0m0.010s

i wanna know how to call out this

[Robert Kern]

Re: quetion about &quot;+=&quo t; and &quot;runtime&q uot;

gagaguy@gmail.c om wrote:[color=blue]
> 1.i have look " += " up,but i can't find it.[/color]

http://docs.python.org/ref/augassign.html

[color=blue]
> is it ofthen used?[/color]

Reasonably so.
[color=blue]
> 2.i saq a result like this in a web page:
>
>
> $ time python permute2.py 56789 3
> Got 120 items.
> Maximum at 87596 ,product 84000
>
> real 0m0.057s
> user 0m0.050s
> sys 0m0.000s
>
> $ time python permute3.py 56789 3
> Got 120 items.
> Maximum at 87596 ,product 84000
>
> real 0m0.040s
> user 0m0.030s
> sys 0m0.010s
>
> i wanna know how to call out this[/color]

As Terry said, look at the "time" module. Don't use the "time" program
(a standard program on UNIX-like systems) unless you actually want to
time the startup of the interpreter too rather than just the code itself.

--
Robert Kern
rkern@ucsd.edu

"In the fields of hell where the grass grows high
Are the graves of dreams allowed to die."
-- Richard Harter