Basics of MATLAB and Beyond

We can plot the surface z as a function of x and y:mesh(x,y,z)We can expand the domain of the calculation by increasing the inputto meshgrid. Be careful to end the lines with a semicolon to avoid beingswamped with numbers:[x,y] = meshgrid(-10:10);z = sqrt(x.^2 + y.^2);mesh(x,y,z)The surface is an inverted cone, with its apex at (0, 0, 0).Companion M-Files Feature 3 A clearer plot can be producedusing a polar grid, instead of a rectilinear grid. We can use thecompanion function polarmesh to produce such a plot. First wedefine a polar grid of points:[r,th] = meshgrid(0:.5:10,0:pi/20:2*pi);Then display the surface defined by z = r:polarmesh(r,th,r)A more interesting surface isz = 3(1 − x) 2 e −x2 −(y+1) 2 − 10( 1 5 x − x3 − y 5 )e −x2 −y 2 ···− 1 −y 23 e−(x+1)2 .In matlab notation you could type:c○ 2000 by CRC Press LLC