Equ_Select - Texas Instruments TI-89 Developer's Manual

Appendix A: System Routines — Graphing

EQU_select

Declaration: BOOL EQU_select (SSHORT cFunc , EQU_SELECT sel )
Category(ies): Graphing
Description: Turn on/off/toggle function graph selection flag. This controls which
functions have a check mark by them in the Y= screen and subsequently
are graphed in the Graph screen.
This routine uses the current Graph mode setting to determine which type
of functions are affected.
Inputs: cFunc — Function number to select/deselect (1 . . . 99).
sel
Outputs: Return TRUE if the graph function exists, otherwise return FALSE.
Assumptions: 3D graph mode expects no more than one function to be selected. If you select
a 3D function to graph, make sure you deselect all other 3D functions.
Side Effects: None
Availability: All versions of the TI-89 / TI-92 Plus.
TI-89 / TI-92 Plus
Differences: None
See Also: EQU_setStyle
Example:
BOOL selectfunc(SSHORT cFunc)
{
Access_AMS_Global_Variables;
BOOL bSel;
bSel = EQU_select(cFunc, SELECT_ON);
if (gr_active->graph_mode == GR_3D && bSel) /* 3D mode and was func selected? */
{
SSHORT n;
for (n = 1; n <= 99; n += 1)
{
if (n != cFunc)
EQU_select(n, SELECT_OFF);
}
}
return bSel;
}
TI-89 / TI-92 Plus Developer Guide
Parametric graph mode allows functions yt1 . . . yt99 to be
selected by specifying function numbers -1 . . . -99.
— SELECT_ON to graph function.
SELECT_OFF to deselect function from graph.
SELECT_TOGGLE to toggle function selection.
Not for Distribution
/* select function to graph */
/* deselect all other functions */
/* except one just selected */
Beta Version January 26, 2001
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