These problems are from the paper: J. O. Coleman, ``Systematic Mapping of Quadratic Constraints on Embedded FIR Filters to Linear Matrix Inequalities,'' Proc. 1998 Conf. on Information Sciences and Systems, Princeton University, March 1998.
The first problem is an LP, the next three are SOCPs, and the last is a nonconvex NLP. Each model writes one or more output files that can be displayed, for example, with gnuplot.
Model 3.mod involves splitting a digital audio signal
into three components, a low frequency component
(called woofer), a mid frequency component (called midrange)
and a high frequency component (called tweeter).
The plot shown below was produced with gnuplot
using the following command:
plot "3w.out" w lines, "3m.out" w lines, "3t.out" w lines
Model 3a.mod is a slight stylistic improvement on
3.mod. It also uses more realistic breakpoints for the
three components. You can listen to various snippets of Pink Floyd's
"Money" by selecting the appropriate choice below: