plsurf3d
(x, y, z, nx, ny, opt, clevel, nlevel); 
Plots a three dimensional shaded surface plot within the environment set up
by plw3d
. The surface is defined by the twodimensional array
z
[nx
][ny
],
the point z
[i][j] being the
value of the function at (x
[i],
y
[j]). Note that the points in
arrays x
and
y
do not need to be equally
spaced, but must be stored in ascending order.
For further details see the Section called Three Dimensional Surface Plots in Chapter 3.
x
(PLFLT *, input)
Pointer to set of x coordinate values at which the function is
evaluated.
y
(PLFLT *, input)
Pointer to set of y coordinate values at which the function is
evaluated.
z
(PLFLT **, input)
Pointer to a vectored twodimensional array with set of
function values.
nx
(PLINT, input)
Number of x values at
which function is evaluated.
ny
(PLINT, input)
Number of y values at
which function is evaluated.
opt
(PLINT, input)
Determines the way in which the surface is represented. To specify
more than one option just add the options, e.g. FACETED + SURF_CONT
opt =FACETED: Network
of lines is drawn connecting points at which function is
defined.
opt =BASE_CONT: A contour
plot is drawn at the base XY plane using parameters
nlevel and clevel .
opt =SURF_CONT: A contour
plot is drawn at the surface plane using parameters
nlevel and clevel .
opt =DRAW_SIDES: draws a curtain
between the base XY plane and the borders of the plotted function.
opt =MAG_COLOR:
the surface is colored according to the value of Z; if
MAG_COLOR is not used, then the default
the surface is colored according to the intensity of the
reflected light in the surface from a light source whose
position is set using pllightsource .
clevel
(PLFLT *, input)
Pointer to the array that defines the contour level spacing.
nlevel
(PLINT, input)
Number of elements in the clevel array.

Redacted form: plsurf3d(x, y, z, opt, clevel)
This function is used in example 8.