Texas Instruments TI-89 Developer's Guide

Appendix A: System Routines — Algebra Utilities
237
TI
-
89 / TI
-
92 Plus Developer Guide
Not for Distribution
Beta Version January 26, 2001
has_different_variable
Declaration:
Boolean
has_different_variable
(EStackIndex
i
, EStackIndex
vi
,
Boolean
ignore_func
)
Category(ies):
Algebra Utilities
Description:
i
indexes an expression and
vi
indexes a variable or list thereof. Returns
TRUE if the expression has another variable. Otherwise returns FALSE. If
ignore_func
is TRUE, user-function names are treated as variables.
Inputs:
i
—
Indexes the top tag of an internally-simplified algebraic
expression.
vi
—
Indexes the top tag of a variable or of a list thereof.
ignore_func
—
TRUE if user-function names should be treated as
variables.
Outputs:
Returns TRUE if the expression has another variable. Otherwise returns
FALSE.
Assumptions:
None
Side Effects:
None
Availability:
All versions of the TI
-
89 / TI
-
92 Plus.
TI
-
89 / TI
-
92 Plus
Differences:
None
See Also: main_gen_var_index, next_var_or_kernel_index, push_var_kern_tail
Example:
Returns
ignore_func
if
i
indexes x + f(x) and
vi
indexes x.
push_quantum (8u);
vi = top_estack; /* vi becomes variable x */
push_quantum (9u); /* Push variable y */
has_different_variable (top_estack, vi, FALSE); /* Returns TRUE */

Texas Instruments TI-89 Specifications

General

Display size (HxV)	100 x 160 mm
Memory type	639K FLASH ROM, 188K bytes RAM
Compatible operating systems	Operating System 2.09
Battery type	AAA