Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2007
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2007

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Slow Show/Graphics in v6.0

  • To: mathgroup at smc.vnet.net
  • Subject: [mg80988] Re: [mg80906] Slow Show/Graphics in v6.0
  • From: Alex Shvydky <ashv at lle.rochester.edu>
  • Date: Fri, 7 Sep 2007 02:04:29 -0400 (EDT)
  • References: <200709050653.CAA26889@smc.vnet.net> <377175200709051434pb7ae575gfe4e7574f72f4379@mail.gmail.com>

Thanks for the input, Ricardo.

They should do something with that. Currently I am running both 5.2 and 
v6.0 side by side
and for now most of the code is noticeably slower in 6.0! To the point 
it is not usable anymore.
(Of course I could spent couple of days to optimize its etc. etc., but 
then it would defeat
the purpose of using Mathematica in the first place - I would rather 
then do it in Fortran
or C...)

Like e.g.

profr[r_, s_] := E^(Log[0.05]*r^s);
fonebeam[th_, s_] := profr[Sin[th], s]*Max[0, Cos[th]];
lmax = 10;
Table[
    Interpolation[({#1, fonebeam[#1, s]} &) /@  Range[0, Pi, 
Pi/(30.*lmax)]];
    NIntegrate[finterp[th]*LegendreP[#1, Cos[th]]*Sin[th], {th, 0, Pi}, 
MaxRecursion -> 16] & /@ Range[0, lmax],
{s, 1.9, 3., 0.02}];

took 3.78sec in Mathematica V5.2 and 39.97sec in V6.0.

There is again an order of magnitude slow down!

I am observing this across the board. Whatever the "improvement" they 
introduce in
my view can not justify an order of magnitude slow down!
I hope they work on that and v6.xx will be faster.

It is like a new version or a C or Fortran compiler would come with 10 
times larger libraries and features,
but the code it would generate from your old programs would run 10 times 
slower.

Alex




Ricardo Samad wrote:
> Dear Alex,
>
> I confirm that some graphic functions rendering became slower in 
> Mathematica 6.0.
> I am having a similar problem when trying to display a 480 x 640 data 
> array using ListContourPlot or ListPlot3D; In Mathematica 5.2 it took 
> a few seconds, in 6.0 it takes minutes, and eventually the Kernel hangs.
> I also would like to know if there´s a setting to speed the rendering up.
>
> Ricardo Samad
>
>
>
> On 9/5/07, *Alex Shvydky* <ashv at lle.rochester.edu 
> <mailto:ashv at lle.rochester.edu>> wrote:
>
>     Hello,
>
>     Just wanted to share my puzzlement (utter disappointment/
>     frastration) with a ridiculously slow speed of Show/Graphics
>     routines in the v6.0 of Mathematica as compared to 5.2,
>     which to me at this point makes v6.0 plain unusable.
>
>     Working with hydrodynamic simulations I need to
>     visualize the computational grid. So I wrote
>     simple Mathematica routines to draw a simulation grid.
>     In 5.2 they worked fabulously for the past couple of
>     years.
>
>     Here's an example.
>     First, set up two 2dimensional x- and y-coordinate
>     arrays.
>
>     Timing[
>        mr = 350;
>        mt = 350;
>        xar = Table[((ir - 1.)/(mr - 1.))*Cos[Pi*((it - 1.)/(mt - 1.))],
>                    {it, 1, mt}, {ir, 1, mr}];
>        yar = Table[((ir - 1.)/(mr - 1.))*Sin[Pi*((it - 1.)/(mt - 1.))],
>                    {it, 1, mt}, {ir, 1, mr}];
>     ]
>
>     In v6.0 it took
>     Out[3]= {2.312, Null}
>     In v5.2 it took
>     {0.281 Second, Null}
>
>     Which is an order of magnitude difference, but hold on.
>     Now let's plot the mesh by simply constructing table
>     of edges of all the cells (I am aware that the algorithm
>     below is very unoptimized and can be made faster etc. etc.
>     It was not my intention to discuss here what should be the
>     fastest algorithm to plot a 2-d mesh,
>     nor was it my intention to debate the issue why one
>     would need to plot such a large mesh in the first place...,
>     but rather to compare the execution time for an IDENTICAL
>     code on v6.0 and v5.2. and get some confirmation/explanation
>     of such a suspiciously slow execution speed!).:
>
>     Timing[
>     Show[
>         Graphics[{Hue[ 0.7], AbsoluteThickness[0.1],
>             Table[{Line[{{xar[[it,ir]], yar[[it,ir]]},
>                           {xar[[it,ir + 1]],yar[[it,ir + 1]]},
>                           {xar[[it + 1,ir + 1]], yar[[it + 1,ir + 1]]},
>                           {xar[[it + 1,ir]], yar[[it + 1,ir]]}}]},
>              {ir, 1, mr - 1}, {it, 1, mt - 1}]
>         }],
>     PlotRange -> {{-1, 1}, {0, 1}}, AspectRatio -> 1/2, Axes -> True,
>     DisplayFunction -> $DisplayFunction, ImageSize -> 800]]
>
>     While the timing as, it is returned by the Timing[] function,
>     is smaller in the v6.0:
>     {1.703, <Here goes the actual graphics>}
>     vs.
>     {2.094 Second, -Graphics-}
>     in v5.2
>
>
>     The actual cell evaluation time in v.6.0 is 124.11 seconds
>     vs. 2.22 seconds in v 5.2. ???!!!!!!!
>
>     Could anybody please confirm this. Also it would be helpful
>     if someone from Wolfram Research would explain if
>     that is intended (unavoidable) by design or maybe
>     a simple setting (which I am unaware of) or a future patch
>     will be able to fix it.
>
>     Also, it is horribly slow to resize the above graphics
>     in v5.2 you just grab the corned and drag. In v6.0 you
>     must do it 10-100 times slower (is it possible
>     that I just have a very poor graphics card?).
>
>
>     Thanks,
>     Alex Shvydky
>
>
>
>
> -- 
> ____________________________________
> Ricardo Elgul Samad
>
> tel: (+55 11) 3816-9314
> fax: (+55 11) 3816-9315
>
> Centro de Lasers e Aplicações
> IPEN/CNEN-SP
> AV. Prof. Lineu Prestes 2242
> Cidade Universitária
> 05508-000
> São Paulo - SP
> Brazil
> ____________________________________ 

-- 
_______________________________________________________________

Alex Shvydky                           <ashv at lle.rochester.edu>

Research Associate
Computational Design Group

Laboratory for Laser Energetics        Office:  1423 COI
University of Rochester                Phone:  (585) 275-9539
250 East River Road                    FAX:    (585) 275-5960
Rochester NY  14623
_______________________________________________________________



  • Prev by Date: Re: Slow Show/Graphics in v6.0
  • Next by Date: Re: Bug with 3D graphics lines
  • Previous by thread: Re: Slow Show/Graphics in v6.0
  • Next by thread: Re: Re: Slow Show/Graphics in v6.0