Re: [Visualpython-users] Does Glowscript have numpy-like performance?

[Bruce S. <Bru...@nc...>]

I was wrong. Firefox on my Windows 7 machine is also a 32-bit
application, but it runs the gas program about twice as fast as
Chrome. I also see the higher speed in Safari on a Macbook Pro of
comparable speed.

Bruce Sherwood

On Fri, Jun 8, 2012 at 3:49 PM, Bruce Sherwood <Bru...@nc...> wrote:
> Correction: I made my measurements with Chrome on a 64-bit Windows
> machine, unaware that Chrome runs slowly on 64-bit machines because it
> is a 32-bit application. Here are improved measurements, copied from
> comments in the GlowScript program:
>
> On a 32-bit Windows computer running Chrome: VPython gas.py with 100
> atoms, dt = 1e-5, rate(100), no graphing: 100 iterations = 1 second.
>
> The similar Glowsript program with same conditions: 100 iterations =
> 4.5 seconds.
>
> /With rate(300), VPython is 0.35 s, GlowScript remains 4.5 s.
>
> Presumably the big difference is the Python numpy library, which runs
> at C speed, and which eliminates some explicit loops.
>
> Note that on a 64-bit Windows computer Chrome runs this program half
> as fast as on a 32-bit computer, because Chrome is a 32-bit
> application. On 64-bit Windows Firefox is a 64-bit application and
> runs the program twice as fast as Chrome.
>
> Bruce Sherwood
>
> On Thu, Jun 7, 2012 at 10:47 PM, Bruce Sherwood <Bru...@nc...> wrote:
>> I've now converted the VPython demo program gas.py to GlowScript:
>>
>> http://www.glowscript.org/#/user/GlowScriptDemos/folder/Examples/program/HardSphereGas
>>
>> To run the program, you need to have a WebGL-enabled browser and a
>> modern graphics card. For details, see the Help at glowscript.org.
>>
>> As for speed, this is what I found:
>>
>> VPython gas.py with 100 atoms, dt = 1e-5, no graphing: 100 iterations
>> = 1.1 seconds. This similar Glowsript program with same conditions:
>> 100 iterations = 11.7 seconds. Presumably the big difference is the
>> Python numpy library, which runs at C speed, and which eliminates some
>> explicit loops.
>>
>> Bruce Sherwood