The function plenv
is used to define the scales and axes for simple
graphs. plenv
starts a new picture on the next subpage (or a new
page if necessary), and defines the ranges of the variables required.
The routine will also draw a box, axes, and numeric labels if
requested.
For greater control over the size of the plots, axis labelling and
tick intervals, more complex graphs should make use of the functions
plvpor
, plvasp
, plvpas
, plwind
, plbox
, and routines for
manipulating axis labelling plgxax
through plszax
.