Page 842 - Mechatronics with Experiments

828 MECHATRONICS

FIGURE A.6: 3D line plot example.

3D surface plots are done by
mesh(x1,y1,z1) ; % 3-d plots with lines
surf(x1,y1,z1) ; % 3-d plots with surface
contour(x1,y1,z1) ; % Generates a contour plot
surfc(x1,y1,z1) ; % 3-d plots with surface and contour
combined
where x1 and y1 form a 2D matrix defining the x-y grid’s coordinates. These data are
typically created from row vectors x and y using the

[x1, y1] = meshgrid(x,y)
function. The x1 vector is rows of the x vector, and the y1 vector is the columns of the
2
2
y vector. For example, to evaluate the function x ⋅ e (−x −y ) over the range −1 < x < 1,
−1 < y < 1,
clc ;
clf ;
[X,Y] = meshgrid(-1:.5:1, -1:.5:1)
Z = X.∗ exp(-X.ˆ2 - Y.ˆ2)
surf(X,Y,Z)
>>
X =

-1.0000 -0.5000 0 0.5000 1.0000
-1.0000 -0.5000 0 0.5000 1.0000
-1.0000 -0.5000 0 0.5000 1.0000
-1.0000 -0.5000 0 0.5000 1.0000
-1.0000 -0.5000 0 0.5000 1.0000