This problem demonstrates the use of data ARRAYS in boundary definition.
Coordinate arrays are constructed by functional array definition
and joined in a spline fit to form the system boundary.
title 'wave boundary'
ysine = array for p(0 by 0.1 to 10): sin(2*p)+base
xsine = array for p(0 by 0.1 to 10): p
line to (0,base)
line to (10,0) to close