). Additional input columns may be used
to provide information such as variable point size or line color.
The pointinterval (short form pi) property of the line style can be used to control whether or not every point in the plot is given a symbol. For example, 'with lp pi 3' will draw line segments through every data point, but will only place a symbol on every 3rd point. A negative value for pointinterval will erase the portion of line segment that passes underneath the symbol.
linespoints may be abbreviated lp.