Push_Div_Dif_1C - Texas Instruments TI-89 Developer's Manual

Appendix A: System Routines — Algebra Utilities

push_div_dif_1c

Declaration: void push_div_dif_1c (EStackIndex i , EStackIndex vi , EStackIndex j )
Category(ies): Algebra Utilities
Description: Pushes onto the estack the centered first difference (TI-BASIC function
nDeriv) of the expression indexed by i , with respect to the variable indexed
by vi , using the expression indexed by j as the step size.
For example: nDeriv (f(x), x, h) -> (f(x + h) - f(x - h))/(2h).
If invoked via the push_internal_simplify function, vi then i are simplified
to deepest variable. However, if the deepest variable value of vi has a
such-that or § value, that value is substituted for the deepest variable
value after computing the first difference.
For example, nDeriv (x^3, x, h) | x = 1 -> h^2 + 3.
i
Inputs:
vi
j
Outputs: None
Assumptions: None
Side Effects: None
Availability: On AMS 2.02 and higher.
TI-89 / TI-92 Plus
None
Differences:
See Also: push_div_dif_1f
Example:
push_Float (1e-4);
h = top_estack;
push_quantum (8u);
vi = top_estack; /* Push variable x */
push_quantum (EXP_TAG);
push_div_dif_1c (top_estack, vi, h);
TI-89 / TI-92 Plus Developer Guide
— Index of the top tag of an internally-simplified algebraic
expression, comparison or aggregate thereof.
— Index of a variable.
— Index of the top tag of an internally-simplified algebraic expression
or an aggregate thereof.
/* top_estack -> e^x */
/* push nDeriv(e^x, x, 1e-4) */
Not for Distribution
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Beta Version January 26, 2001