Texas Instruments TI-89 Titanium User Manual

3D Graphing 373
How the Viewing Angle Is Measured
Note: When eyeψ=0, the z axis is vertical on the screen. When eyeψ=90, the z axis is
rotated 90¡ counterclockwise and is horizontal.
In the Window Editor (8$), always enter
eyeq, eyef, and eyeψ in degrees,
regardless of the current angle mode.
The viewing angle has three components:
•
eyeq — angle in degrees from the
positive x axis.
•
eyef — angle in degrees from the
positive z axis.
•
eyeψ — angle in degrees by which the
graph is rotated counter-clockwise
around the line of sight set by
eyeq
and
eyef.
Y
Z
X
eyeq
eyef
eye
Do not enter a ¡symbol. For
example, type 20, 70, and
0, not 20
¡, 70¡ and 0¡.

Texas Instruments TI-89 Titanium Specifications

General

Display Type	LCD
Display Resolution	160 x 100 pixels
CPU	Motorola 68000
CPU Speed	16 MHz
RAM	256 KB
Flash ROM	2.7 MB
Programming Language	TI-BASIC, Assembly
Power Source	4 AAA batteries
Connectivity	I/O port
Dimensions	7.5 x 3.5 x 1 inches