*To*: mathgroup@smc.vnet.net*Subject*: [mg10326] Re: Mathematica Plot [help]*From*: Paul Abbott <paul@physics.uwa.edu.au>*Date*: Thu, 8 Jan 1998 23:40:50 -0500*Organization*: University of Western Australia*References*: <68s834$5mq@smc.vnet.net>

Wei Xu wrote: > I want to draw a surface, say sin[x,y], defined on a triangular domain, > say, x:[0,1], y:[0,1] and x+y <=1. > I tried to use the following command: > ParametricPlot3D[{fx, fy, fz}, {x,0,1}, {y,0,1-x}] but it is not > allowed to use {y,0,1-x}. An answer for this appeared in The Mathematica Journal 5(1):15. Change variables and reparametrise y: ParametricPlot3D[{x,u (1-x),Sin[x u (1-x)]},{x,0,1},{u,0,1}]; Here y -> u (1-x) and u:[0,1]. Cheers, Paul ____________________________________________________________________ Paul Abbott Phone: +61-8-9380-2734 Department of Physics Fax: +61-8-9380-1014 The University of Western Australia Nedlands WA 6907 mailto:paul@physics.uwa.edu.au AUSTRALIA http://www.pd.uwa.edu.au/~paul God IS a weakly left-handed dice player ____________________________________________________________________