The most comprehensive plotting routine available is AST_GRID, which can be used to draw labelled coordinate axes and, optionally, to overlay coordinate grids on the plotting area (Figure ). The routine is straightforward to use, simply requiring a pointer to the Plot and a STATUS argument:
CALL AST_GRID( PLOT, STATUS )
It will draw both linear and curvilinear axes and grids, as required
by the particular Plot. The appearance of the output can be modified
in a wide variety of ways by setting various Plot attributes.
The Label attributes of the current Frame are displayed as the axis
labels in the grid, and the Title attribute as the plot title. Sub-strings
within these strings can be given different appearances, or turned into
super-scripts or sub-scripts, by the inclusion of escape sequences (see
section ) within the Label attributes.
AST A Library for Handling World Coordinate Systems in Astronomy