These routines are involved in making (line) plots.
Produce a contour plot.
Transform between various plot and window-related coordinate systems.
Erase the screen.
Set or show limits on the plot coordinate ranges.
Add another plot to an existing one.
Set the plot device.
Set the pen width.
Produce a plot.
Draw a line.
The following routines are involved in creating 3D plots (currently under development).
Scale a 3D plot so it fits the screen.
Produce a 3D plot.
Project a 3D plot data point into screen coordinates.
Set the 3D projection parameters.