I can use plotSetXTicInterval to control the tics on the x-axis, how do I do the same for Y?
Due to its importance for time series, controls for the x-axis (plotSetXTicInterval and plotSetXTicLabel) were implemented before controls for the y-axis. Controls for the y-axis are not yet implemented.
then how do i make the y start from 1-100, when the true range is 20-70?
Ok, now I understand what you want. You don't need to use the 'Tic' functions. Here is a link to a procedure that will allow you to control the extent of the graph.