PGPLOT Module: PGRNGE -- choose axis limits

SUBROUTINE PGRNGE (X1, X2, XLO, XHI)
REAL X1, X2, XLO, XHI

Choose plotting limits XLO and XHI which encompass the data
range X1 to X2.


Arguments
X1, X2 (input) : the data range (X1 to be plotted.
XLO, XHI (output) : suitable values to use as the extremes of a graph
axis (XLO <= X1, XHI >= X2).