function [bpx,bpy,wfxy] = crule2d (nquadx,nquady)
%usage:  [bpx,bpy,wfxy] = crule2d (nquadx,nquady);
[bpxv,wfxv]=crule(nquadx);
[bpyv,wfyv]=crule(nquady);
[bpx,bpy]=meshgrid(bpxv,bpyv);
[wfx,wfy]=meshgrid(wfxv,wfyv);
wfxy=wfx.*wfy;