Texas Instruments TI-89 ユーザーズマニュアル
3D Graphing
387
How the Viewing Angle Is Measured
How the Viewing Angle Is Measured
How the Viewing Angle Is Measured
How the Viewing Angle Is Measured
Note:
When
eye
ψ
=0
, the z axis is vertical on the screen. When
eye
ψ
=90
, the z axis is
rotated 90¡ counterclockwise and is horizontal.
In the Window Editor (
8 $), always enter
eye
q,
eye
f, and
eye
ψ
in degrees,
regardless of the current angle mode.
The viewing angle has three components:
•
eye
q — angle in degrees from the
positive x axis.
•
eye
f — angle in degrees from the
positive z axis.
•
eye
ψ
— angle in degrees by which the
graph is rotated counter-clockwise
around the line of sight set by
around the line of sight set by
eye
q
and
eye
f.
Y
Z
X
eye
q
eye
f
eye
Do not enter a
¡
symbol. For
example, type 20, 70, and
0, not 20
0, not 20
¡
, 70
¡
and 0
¡
.