Texas Instruments TI89 Developer Guide - Page 878

836 Appendix A: System Routines - Math push_standardize Declaration: void push_standardize (EStackIndex i) Category(ies): Math Description: Pushes onto the estack an equivalent expression in which for all sums at all recursive levels: • The sums contain no negative exponents or monomial factors. • The leading coefficient is positive. • If the numeric factors of the terms are all exactly-representable whole numbers, then the gcd these numeric factors is 1. Otherwise the leading coefficient is 1.0. This is the minimum level of factorization. It includes forming common denominators. To within further factorization of sums, it standardizes expressions so that similar factors are more likely to be recognized. Examples: x^-1 † (y^2 † L6 + y † 4) + 5 -> (x † 5 + (y † 3 + L2) † y † L2) † x^L1 x^-1 † (y^2 † L6.0 + y † 4) + 5 -> (x † 5 + (y † 3.0 + L2) † y † L2) † x^L1 x^-1 † (y^2 † L1.2 + y † 4) + 5 -> (x + (y + L3.333 y † L.24) † x^L1 † 5.0 Inputs: i - Indexes the top tag of an internally-simplified algebraic expression. Outputs: None Assumptions: None Side Effects: None Availability: On AMS 2.02 and higher. TI-89 / TI-92 Plus Differences: None See Also: push_factor, push_comdenom push_quantum_as_nonnegative_int(2u); exponent = top_estack; push_quantum (8u); /* Push variable x */ replace_top2_with_pow (exponent); power = top_estack; /* x^2 */ push_quantum (8u); /* Push variable x */ replace_top2_with_sum (power); /* top_estack -> x^2 + x */ push_standardize (top_estack); /* Pushes (x + 1)*x */ TI-89 / TI-92 Plus Developer Guide Not for Distribution Beta Version January 26, 2001