# Three-dimensional Graphics; The Variable Eq; Examples Of Interactive Plots Using The Plot Menu - HP 48gII User Manual

Graphing calculator.

## Three-dimensional graphics

The three-dimensional graphics available, namely, options Slopefield,
Wireframe, Y-Slice, Ps-Contour, Gridmap and Pr-Surface, use the VPAR
variable with the following format:
{x
, x
, y
, y
left
right
near
y
, z
, x
, y
eye
eye
step
step
These pairs of values of x, y, and z, represent the following:
Dimensions of the view parallelepiped (x
)
z
, z
low
high
Range of x and y independent variables (x
Location of viewpoint (x
Number of steps in the x- and y-directions (x
Three-dimensional graphics also require the PPAR variable with the
parameters shown above.

### The variable EQ

All plots, except those based on ΣDAT, also require that you define the
function or functions to be plotted by storing the expressions or references to
those functions in the variable EQ.
In summary, to produce a plot in a program you need to load EQ, if required.
Then load PPAR, PPAR and ΣPAR, or PPAR and VPAR. Finally, use the name
of the proper plot type: FUNCTION, CONIC, POLAR, PARAMETRIC, TRUTH,
DIFFEQ, BAR, HISTOGRAM, SCATTER, SLOPE, WIREFRAME, YSLICE,
PCONTOUR, GRIDMAP, or PARSURFACE, to produce your plot.

### Examples of interactive plots using the PLOT menu

To better understand the way a program works with the PLOT commands and
variables, try the following examples of interactive plots using the PLOT menu.
Example 1 – A function plot:
„ÌC
@) P TYPE @FUNCT
'√r' `„ @@EQ@@
, z
, z
, x
far
low
high
min
}
left
min
)
, y
, z
eye
eye
eye
step
Select FUNCTION as the plot type
Store function '√r' into EQ
, x
, y
, y
, x
max
min
max
, x
, y
, y
right
near
)
, x
, y
, y
max
min
max
)
, y
step
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,
eye
,
far