Re: [Visualpython-users] vpython crashes python

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

This may not be entirely relevant, but I note that Visual is not as 
flexible as it ought to be in specifying x and y in a gdisplay. Your 
program works on my Windows machine only after changing x=0.0 to x=0 and 
y-0.0 to y=0 in display1 = gdisplay(.....). It makes sense for these 
pixel arguments to be integers, but it's silly/wrong not to accept 0.0.

However, I don't see how this issue relates to the problems you're 
seeing. The only thing I can think of would be that you could try 
updating the graphics driver on your machine. Sometimes an old driver 
has problems with OpenGL.

Bruce Sherwood

Fred Sells wrote:
> I'm running XP with all patches uptodate.  Same problem with python 
> 2.4.4 and 2.5.1.
> 
> A simple demo program crashes python.  I checked site-packages and it 
> has numarray, numpy, Numeric and visual folders
> 
> I'm trying some sample code from the web site (attached) and get this 
> useless error (attached) to notify microsoft of the crash.  It's greek 
> to me, but perhaps it means something to the guru's here.
> I also get this erroneous python error, so I wonder if the python.exe is 
> hosed. but I've installed/reinstalled several times.  I've tried running 
> from within Eclipse and from command line with the same results.
> 
> On my computer at work, no problem with python 2.4.4.  I don't know what 
> to try next.  I'm running this on an older laptop PIII 1.2Ghz with 512M 
> RAM if that matters.
> 
>   for x in range(x_start, x_end, 0.1):
> Traceback (most recent call last):
>   File "C:\all\projects\calculus\src\chartfunction.py", line 20, in <module>
>     for x in range(x_start, x_end, 0.1):
> ValueError: range() step argument must not be zero
> 
> 
> 
> ------------------------------------------------------------------------
> 
> from visual.graph import * # import graphing features
> import sys 
> display1 = gdisplay(x=0.0, y=0.0, width=300, height=200,
>           title='Cos Graph', xtitle='X', ytitle='Y',
>           xmax=10., xmin=-10., ymax=3., ymin=-3.,
>           foreground=color.black, background=color.white)
> 
> #display2 = gdisplay(x=0, y=200, width=300, height=200,
> #          title='Sin Graph', xtitle='X', ytitle='Y',
> #          xmax=10., xmin=-10., ymax=3., ymin=-3.,
> #          foreground=color.black, background=color.white)
> 
> graph = gcurve(gdisplay=display1,color=color.cyan) # a connected curve object
> #graph2 = gcurve(gdisplay=display2,color=color.blue)
> 
> 
> x_start= -8.   # graph starting from this x value
> x_end = 8.     # graph ending at this x value
>  
> for x in range(x_start, x_end, 0.1):
>     y = cos(x) # the function we want to graph  
>     print x,y
>     continue 
>     graph.plot(pos=(x,y)) # plots a point
> 
> #    y = sin(x) # the function we want to graph   
> #    graph2.plot(pos=(x,y)) # plots a point
>