According to the TI-81 Guidebook, in order to draw a histogram
(Xmax-Xmin)/Xscl must be greater than or less than 36.
This program fixs the scaling so that a histogram can be drawn
and if you want it to it will draw the histogram.
Takes up 79 bytes.
Prgm:HIST.SCL
:ClrHome
:If Xscl=o
:1→Xscl
:Lbl 1
:If ((Xmax-Xscl)/Xscl>36
:Xscl+1→Xscl
:If ((Xmax-Xscl)/Xscl>36
:Goto 1
:Disp "1)Y 2)N"
:Disp "Hist"
:Input H
:If H=2
:End
:ClrDraw
:Hist