function pzslice(x,y,u,cax)
% PZSLICE plots a zslice from ECOMSI using PCOLOR
%  USAGE: pzslice(x,y,u,cax)
% x is array of x points
% y is array of y points 
% u is array of data
% cax is range of data to map 
% EXAMPLE:  pzslice(x,y,temp,[10 22])  plots the variable temp from 10 to 22 deg
ind=find(~isnan(u));
u(ind)=max(u(ind),cax(1));
u(ind)=min(u(ind),cax(2));
clegend4(cax');pcolor(x,y,u);colormap('jet');...
shading('interp');caxis(cax);set(gca,'aspectratio',[NaN 1])
