Push_Difference - Texas Instruments TI-89 Developer's Manual

Appendix A: System Routines — EStack Arithmetic

push_difference

Declaration: void push_difference (EStackIndex i , EStackIndex j )
Category(ies): EStack Arithmetic
Description: Pushes onto the estack the internally-simplified difference of the
expression indexed by i minus the expression indexed by j . If one operand
is a scalar and the other is a square matrix, the scalar is distributed only
over the diagonal of the matrix.
Inputs: i, j — Index of top tags of internally-simplified algebraic expressions,
Outputs: None
Assumptions: None
Side Effects: None
Availability: On AMS 2.02 and higher.
TI-89 / TI-92 Plus
None
Differences:
See Also: push_sum, replace_top2_with_sum, add_to_top, subtract_from_top,
replace_top2_with_difference, add1_to_top, subtract1_from_top,
push_arg_plus_1, push_arg_minus_1
Example:
void push_coef_list (EStackIndex i, EStackIndex ki)
/* i indexes a polynomial in the variable or kernel indexed by ki.
Pushes a tail of its coefficients (including zero-coefficients),
with the constant coefficient deepest.
*/
{ Access_AMS_Global_Variables;
EStackIndex j, ans;
push_quantum (END_TAG);
ans = top_estack;
push_expression (i);
i = top_estack;
while (! is_independent_of (i, ki))
{ push_substitute_simplify (i, ki, Integer0Index);
j = top_estack;
push_difference (i, j);
divide_top (ki);
ans = j - deleted_between (ans, i);
i = top_estack;
}
}
TI-89 / TI-92 Plus Developer Guide
algebraic comparisons, or aggregates thereof.
Not for Distribution
489
Beta Version January 26, 2001