set xlint interval
Specifies the interval between labeled tick marks on the X-axis.
interval is a positive value, the labeled tick marks will 'start' at 0, regardless of the current dimension environment. For example, if you set the interval to 3, the labeled tick marks will be at 0, 3, 6, 9 ...
interval is a negative value, the labeled tick marks will 'start' at the axis start value, which is usually the lower limit of the X dimension environment. If this were 30 (with an interval of 10), then the labeled tick marks would be at 30, 40, 50, 60...
set xlevs command.
set xaxis command.
set xlint and set ylint may not work as described when used to control grid lines for polar stereographic projections.