Compare_Numbers - Texas Instruments TI-89 Developer's Manual

Appendix A: System Routines — EStack Arithmetic

compare_numbers

Declaration: int compare_numbers (EStackIndex i , EStackIndex j )
Category(ies): EStack Arithmetic
Description: Compares the two numbers indexed by i and j .
Inputs: i, j — Indexes to tagged numbers.
Outputs: Returns 0 if the numbers indexed by i and j are equal, even if one is Float
and one is rational. Returns a positive integer if the number indexed by i is
greater than the number indexed by j . Returns a negative integer if the
number indexed by i is less than the number indexed by j . For this function,
all zeros are considered equal: 0 = +0 = L0 = +0.0 = L0.0 = 0.0.
Assumptions: i and j point to the numeric tags of tagged numbers. Note that PI_TAG and
IM_RE_TAG are not considered numeric tags.
Side Effects: Might temporarily push items onto the estack.
Availability: On AMS 2.02 and higher.
TI-89 / TI-92 Plus
Differences: None
See Also: compare_Floats, compare_complex_magnitudes,
compare_expressions
Examples:
/* Return j if it indexes a larger magnitude number than k indexes.
Otherwise return k: */
return compare_numbers(j,k) > 0 ? j : k;
TI-89 / TI-92 Plus Developer Guide Not for Distribution
467
Beta Version January 26, 2001