Fill between two curves
How can I fill between two curves?
A script has been contributed by Wiemin Wang and Steve Hankin thatuses the POLYGON command to fill between two curves, or a curve and a constant value. The text at the start of the script explains its arguments.
Use the script, fill_between.jnl. It is one of the go scripts included with Ferret. For example,
yes? DEFINE AXIS/Z=1:100:1 z100
yes? LET zz = z[gz=z100]
yes? LET a = SIN(zz/10)- zz/50
yes? LET b = 3 + COS(zz/4)
yes? PLOT a,b
yes? GO fill_between POLY/OVER/NOLABEL/PALETTE=blue a z100 b
Continuing, to make the figure on the right above, we fill betweenthe curve defined by variable b and the vertical line at 3.0. Overlay the curves a and b again for clarity.
yes? GO fill_between POLY/OVER/NOLABEL/PALETTE=yellow b z100 3.
yes? PLOT/OVER/NOLAB/COLOR=black a
yes? PLOT/OVER/NOLAB/COLOR=red b