Needing Help in something simple



El jue, 20-06-2013 a las 10:19 -0300, Marcelo Augusto Soares Rodrigues
escribi?:
> What is wrong?
> 
> 
> taca:parametric_surface(x,y(6.5*cos(t)),z(6.5*sin(t)),x,-2,2,t,0,2*%
> pi);
> 
> 
> wxdraw3d(surface_hide = true,color = blue,axis_3d = false,xtics =
> false,ytics = false,ztics = false,view = [90,30], taca);
> 
> 
> 
> 
> All i want is:
> 
> 
> 
> 
>  "x" = x
>  "y" = 6.5*cos(t)
>  "z" = 6.5*sen(t)

Marcelo,

Remove y() and z() and write expressions directly; this should work:

draw3d(parametric_surface(x,6.5*cos(t),6.5*sin(t),x,-2,2,t,0,2*%pi));

--
Mario