RegionPlot ?

*To*: mathgroup at smc.vnet.net*Subject*: [mg23489] RegionPlot ?*From*: "Seth Chandler" <SChandler at uh.edu>*Date*: Fri, 12 May 2000 22:54:28 -0400 (EDT)*Organization*: University of Houston*Sender*: owner-wri-mathgroup at wolfram.com

Right now, the function Experimental`CylindricalAlgebraicDecomposition yields a list of inequalities. For inequalities with two variables, I would like to be able to plot the region showing where that inequality is satisfied. By way of simple example: In[69]:= ecad = Experimental`CylindricalAlgebraicDecomposition[{x + y <= 3, x - y > -4, x >= 0, y >= 1}, {x, y}] Out[69]= 0 <= x < 2 && 1 <= y <= 3 - x || x == 2 && y == 1 What I would like to do is something like: RegionPlot[ecad,{x,-3,5},{y,-3,7}]. The output would be Polygon primitives, Line primitives, and a Point primitive Any thoughts on how to implement this? Obviously, one could approximate the matter by creating a table of x,y values and plotting at {x,y} a primitive of some shape and size for each table element satisfying the set of inequalities. I was hoping someone might come up with something more elegant, however. (Maybe ContourPlot used in some way?)