Push_Substitute_Using_Such_That - Texas Instruments TI-89 Developer's Manual

Appendix A: System Routines — Algebra Utilities

push_substitute_using_such_that

Declaration: void push_substitute_using_such_that (EStackIndex i , EStackIndex vi ,
EStackIndex val )
Category(ies): Algebra Utilities
Description: Substitutes a value for a variable throughout an expression.
i
Inputs:
vi
val — EStackIndex of the value to substitute.
Returns the fully simplified, internal tokenized form of i after substituting val
Outputs:
for each occurrence of vi . Any pre-existing assigned value or substitution
value for vi will be ignored during this operation.
Assumptions: None
Side Effects: May cause estack expansion, heap compression, or throw errors
associated with the full simplification of the expression.
Availability: On AMS 2.04 and higher.
TI-89 / TI-92 Plus
Differences: None
See Also: NG_such_that_index
Example:
If i indexes the bolded tag in the expression x + 1 as follows
1 1 NONNEGATIVE_INTEGER_TAG X_VAR_TAG ADD_TAG
and j indexes the bolded tag in the variable x as follows
X_VAR_TAG
and k indexes the bolded tag in the value 2 as follows
2 1 NONNEGATIVE_INTEGER_TAG
then
push_substitute_using_such_that (i, j, k);
will substitute 2 for x and then simplify the expression to 3 in the estack such that top_estack
points to the bolded tag.
3 1 NONNEGATIVE_INTEGER_TAG
TI-89 / TI-92 Plus Developer Guide
— EStackIndex of the target expression.
— EStackIndex of a variable.
Not for Distribution
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Beta Version January 26, 2001