10.07.2015 Views

v2007.09.13 - Convex Optimization

v2007.09.13 - Convex Optimization

v2007.09.13 - Convex Optimization

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

F.2. CONIC INDEPENDENCE, CONICI() 651F.2 conic independence, conici()(2.10) The recommended subroutine lp() (F.2.1) is a linear program solver(simplex method) from Matlab’s <strong>Optimization</strong> Toolbox v2.0 (R11). Laterreleases of Matlab replace lp() with linprog() (interior-point method)that we find quite inferior to lp() on an assortment of problems; indeed,inherent limitation of numerical precision to1E-8 in linprog() causes failurein programs previously working with lp().Given an arbitrary set of directions, this c.i. subroutine removes theconically dependent members. Yet a conically independent set returned isnot necessarily unique. In that case, if desired, the set returned may bealtered by reordering the set input.% Test for c.i. of arbitrary directions in rows or columns of X.% -Jon Dattorrofunction [Xci, indep_str, how_many_depend] = conici(X,rowORcol,tol);if nargin < 3tol=max(size(X))*eps*norm(X);endif nargin < 2 | strcmp(rowORcol,’col’)rowORcol = ’col’;Xin = X;elseif strcmp(rowORcol,’row’)Xin = X’;elsedisp(’Invalid rowORcol input.’)returnend[n, N] = size(Xin);indep_str = ’conically independent’;how_many_depend = 0;if rank(Xin) == NXci = X;returnend

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!