That may be the problem: I've got Maple 11.0 (build ID 277223) on XP.

Thank you again.  I've just investigated further: it seems to be a bug in 32-bit Windows XP Maple 11.  I've just run your code under linux Maple 11, and there's no problem.

The links below contain your code and another test function:

View 8594_080506rob-israel.mw on MapleNet or Download 8594_080506rob-israel.mw
View file details

Yes, thank you Robert - that does the trick.

My Maple (11) didn't like the y=1..1-x specification in the implicit plot, but could work with y=1..x.  Some of my plots run outside the simplex, but I don't know if this is related to changing the index.

Thank you again.

Colin Rowat

p.s. I get plots outside the simplex with:

g := x -> x + sin(7*Pi*x)/(7*Pi):

Q1 := implicitplot(g(x) + g(y) - g(1-x-y),x=0..1,y=0..1):

Q2 := implicitplot(g(x) - g(y) - g(1-x-y),x=0..1,y=0..1):

Q3 := implicitplot(g(x) - g(y) + g(1-x-y),x=0..1,y=0..1):

display([T(Q1),T(Q2),T(Q3),Simplex]);

Thank you Robert.

Yes, that's the simplex in which I wish to plot.  I want not just to plot the simplex, but functions in it.  In particular, I want to be able to take expressions in a real function, f, defined on (x1,x2,x3) and intersect these with the simplex.

I have therefore been using repeated intersectplot calls to build up a plots[display] call, but wondered if there was a more direct way of doing this.  (I'd like to be able to output to postscript and later convert to something that I can compile in LaTeX; thus, I don't like the implicitly plotted boundaries of the simplex.)

Best,

Colin Rowat