Texas Instruments TI-89 用户手册

3D Graphing

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When you return to FUNCTION graphing mode, your

y(x)

functions are still defined

in the Y= Editor. When you return to 3D graphing mode, your

z(x,y)

equations are

still defined.

Note:

You can use the

Define

command from the Home screen (see the Technical

Reference module) to define functions and equations for any graphing mode, regardless
of the current mode.

Selecting the Display Style

Because you can graph only one 3D equation at a time, display styles are not available.
On the Y= Editor, the Style toolbar menu is dimmed.

For 3D equations, however, you can use:

– or -

8 Í
to set the Style format to WIRE FRAME or HIDDEN SURFACE.

Window Variables

The Window Editor maintains an independent set of Window variables for each Graph
mode setting (just as the Y= Editor maintains independent function lists). 3D graphs use
the following Window variables.

Variable

Description

eye

, eye

eye

Angles (always in degrees) used to view the graph.