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Topic: how to plot a function subject to constraints.
Replies: 14   Last Post: Jan 7, 2013 1:15 PM

 Messages: [ Previous | Next ]
 Emrah Posts: 8 Registered: 12/30/12
Re: how to plot a function subject to constraints.
Posted: Jan 7, 2013 10:48 AM

> Make that
>
> infeasible=~all(G(:)<=0);
>
>

> >
> > Error using horzcat
> > CAT arguments dimensions are not consistent.
> >
> > Error in fplot2 (line 8)
> > G=[g1,g2,g3,g4,g5,g6,g7];
> >
> > any idea?

> ==============
>
> Nope. Don't you expect all g1....g7 to be the same size? If not, it should be obvious to you why it might not be possible to concatenate them. If so, did you check what sizes they are? What happens when use DBSTOP to pause execution at line 8 and do
> "whos g*"

I seperated them and solved it. but still returns empty :(

%calculating constraints
[g1,g2,g3,g4,g5,g6,g7]=constraints(x1,x2,x3,x4);
G1=[g1,g2,g4,g6,g7];
G2=[g3,g5];
infeasible=~all(G1(:)<=0)+all(G2(:)<=0);
x2(infeasible)=nan;
x3(infeasible)=nan;
%objective function
f=1.10471.*x1^2.*x2+0.04811.*x3.*x4.*(14.0+x2);
%constraints are applied to f(x)
f=f*mod_neg_step(g1)*mod_neg_step(g2)*mod_neg_step(g3)*mod_neg_step(g4)...
*mod_neg_step(g5)*mod_neg_step(g6)*mod_neg_step(g7);
%plotting surf
surf(x2,x3,f,'LineStyle','none');

Date Subject Author
12/30/12 Emrah
1/6/13 Emrah
1/6/13 Derek Goring
1/7/13 Emrah
1/7/13 Matt J
1/7/13 Emrah
1/7/13 Matt J
1/7/13 Emrah
1/7/13 Matt J
1/7/13 Emrah
1/7/13 Matt J
1/7/13 Emrah
1/7/13 Matt J
1/7/13 Matt J
1/7/13 Emrah