Texas Instruments TI-89 - Any_Tail

670
Appendix A: System Routines — Lists and Matrices
TI
-
89 / TI
-
92 Plus Developer Guide
Not for Distribution
Beta Version January 26, 2001
any_tail
Declaration:
Boolean
any_tail
(Boolean (*
bool_fun
) (EStackIndex), EStackIndex
i
)
Category(ies):
Lists and Matrices, Math
Description:
Determines whether the
bool_fun
returns TRUE for at least one expression
in the tail of expressions indexed by
i
.
Inputs:
bool_fun
— A Boolean function that takes the index of an expression as
its one argument.
i
— Index of a tail.
Outputs:
Returns TRUE if
bool_fun
returns TRUE for at least one expression in the
tail of expressions indexed by
i
. Otherwise returns FALSE.
Assumptions:
None
Side Effects:
None
Availability:
On AMS 1.05 and higher.
TI
-
89 / TI
-
92 Plus
Differences:
None
See Also: all_tail, map_tail, did_map_aggregate_arg
Example:
Boolean has_inf_mag (EStackIndex i)
/* Returns TRUE if i indexes a real or complex infinity. Otherwise returns FALSE. */
{ EStackIndex j;
return IS_INF_MAG_TAG (ESTACK (i)) ||
IM_RE_TAG == ESTACK (i) &&
(IS_INF_MAG_TAG (ESTACK (i-1u)) &&
IS_INF_MAG_TAG (ESTACK (next_expression_index (i - 1u))) ) ||
LIST_TAG == ESTACK (i) && any_tail (has_inf_mag, i - 1u);
}