HP 50G, User Manual

Page: 724 / 887

Page 22-9
The PTYPE menu within 3D (IV)
The PTYPE menu under 3D contains the following functions:
These functions correspond to the graphics options Slopefield, Wireframe, Y-
Slice, Ps-Contour, Gridmap and Pr-Surface presented earlier in this chapter.
Pressing one of these soft menu keys, while typing a program, will place the
corresponding function call in the program. Press
L
@)@3D@@
to get back to the
main 3D menu.
The VPAR menu within 3D (V)
The variable VPAR stands for Volume PARameters, referring to a parallelepiped
in space within which the three-dimensional graph of interest is constructed.
When press [VPAR] in the 3D menu, you will get the following functions. Press
L
to move to the next menu:
Next, we describe the meaning of these functions:
INFO (S) and VPAR (W)
When you press
@INFO
(S) you get the information shown in the left-hand side
screen shot above. The ranges in Xvol , Yvol , and Zvol describe the extent of the
parallelepiped in space where the graph will be generated. Xrng and Yrng
describe the range of values of x and y, respectively, as independent variables
in the x-y plane that will be used to generate functions of the form z = f(x,y).
Press
L
and
@INFO
(Y) to obtain the information in the right-hand side screen
shot above. These are the value of the location of the viewpoint for the three-
dimensional graph (Xeye, Yeye, Zeye), and of the number of steps in x and y to
generate a grid for surface plots.