MATLAB by rudra pratap

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Graphics
cylinder
generates a cylinder,
ellipsoid
generates an ellipsoid, and
sphere
generates a sphere.
Among these functions, plot3 and comet3 are the 3-D analogs of plot and
comet commands mentioned in the 2-D graphics section. The general syntax for
the plot3 command is
'I__ p_l_o_t_3_(_x_,---,-z-,--,-s-t_ y y _l_e __ o_ _t_i_o_n-' )---,
p
This command plots a curve in 3-D space with the specified line style. The argument
list can be repeated to make overlay plots, just the same way as with the plot
command. A catalog of these functions with example scripts and the corresponding
output is given on pages 196-200. Because the example scripts use a few functions
that we discuss in Section 6.3.3, we postpone the catalog until then.
Plots in 3-D may be annotated with functions already mentioned for 2-D plotsxlabel,
ylabel, title, text , grid, etc., along with the obvious addition of
zlabel. The grid command in 3-D makes the 3-D appearance of the plots better,
especially for curves in space (see Fig. 6.5 for example).
6.3.1 View
The viewing angle of the observer is specified by the command
I view (azimuth, elevation)
where azimuth and elevation are angles specified in degrees. The azimuth is the rotation
about the z-axis measured counterclockwise from the negative y-axis, and the
elevation is the vertical angle measured positive above the xy-plane (see Fig. 6.4).
The default values for these angles are -37.5° and 30° , respectively.
I
Figure 6.4: The viewing angles azimuth and elevation in 3-D plots.
By specifying appropriate values of the azimuth and the elevation, one can plot
the projections of a 3-D object on different 2-D planes. For example, the command
view(90 ,0) puts the viewer on the positive x-axis, looking straight on the yz-plane,
and thus produces a 2-D projection of the object on the yz-plane. Figure 6.5 shows
the projections obtained by specifying different view angles.