
[xc,yc] = meshgrid(xcenter,ycenter);
[xp,yp,zp] = mapc2m(xc,yc);
u = reshape(data(:,2)./data(:,1), mx,my);
v = reshape(data(:,3)./data(:,1), mx,my);
w = reshape(data(:,4)./data(:,1), mx,my);

hold on
quiver3(xp,yp,zp,u',v',w','k')
hold off
