This program will set the screen display for a TI-81 into integer mode, just as if you had typed [ZOOM][8].
It allows you to select the coordinate to be centered on the sceen, and scale the screen by the amount inputted into theta ().
The symbol for storage used in this proram is "->".  Do not confuse it with "Minus" followed by "Greater-Than".

Prgm:INT.ZM
:ClrHome
:Disp "INT ZM"
:Input 
:Disp "X-COORD."
:Input X
:Disp "Y-COORD."
:Input Y
:-4.8+X->Xmin
:4.7+X->Xmax
:->Xscl
:-3.2+Y->Ymin
:3.1+Y->Ymax
:->Yscl
:DispGraph