n=20
m=20
xValues=linspace(0,1,n)
yValues=linspace(0,1,m)
[xGrid yGrid]=meshgrid(xValues,yValues)
heightBoundary=1;
forcing=2;
data=forcing*ones(size(xGrid));
data(1,:)=heightBoundary;
data(m,:)=heightBoundary;
data(:,1)=heightBoundary;
data(:,n)=heightBoundary;
height=simplePoisson(xGrid,yGrid,data);