Plotting a normal vector to a plane in matlab

Question

I\'m trying to plot a vector normal to a plane but it doesn\'t show up as normal.This is the code

[X,Y]=meshgrid(-10:1:10); R=5+2*(X-4)+4*(Y-2); mesh(X,Y,R)

Answer 1

The vector is normal to the plane. The problem is most likely the automatic axis scaling.

Use axis equal to ensure that data units have the same length along each axis.

[X,Y]=meshgrid(-10:1:10);
R=5+2*(X-4)+4*(Y-2);
mesh(X,Y,R)
hold
quiver3(4,2,5,2,4,-1)
hold off
axis equal

With proper axis scaling, your normal vector will appear normal to the plane.