File: parrot.sci

package info (click to toggle)
scilab 2.4-1
  • links: PTS
  • area: non-free
  • in suites: potato, slink
  • size: 55,196 kB
  • ctags: 38,019
  • sloc: ansic: 231,970; fortran: 148,976; tcl: 7,099; makefile: 4,585; sh: 2,978; csh: 154; cpp: 101; asm: 39; sed: 5
file content (25 lines) | stat: -rw-r--r-- 592 bytes parent folder | download 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
 
function [Kopt,gamaopt]=parrot(D,r)
//Given a matrix D partionned as [D11 D12
//                                D21 D22]
//where size(D22)=r=[r1,r2]
//compute a matrix K such that
//largest singular value of [D11 D12
//                           D21 D22+K]
//is minimal (Parrot's theorem)
//F.D. (1990)
//!
// Copyright INRIA
[l,k]=size(D);
l1=1:(l-r(1));
l2=(l-r(1)+1):l;
k1=1:(k-r(2))
k2=(k-r(2)+1):k;
D11=D(l1,k1);
D12=D(l1,k2);
D21=D(l2,k1);
D22=D(l2,k2);
D1=[D11,D12];D2=[D11;D21];
gamaopt=maxi( maxi(svd(D1)),maxi(svd(D2)) );
Kopt=-D22-D21*inv(gamaopt*gamaopt*eye-D11'*D11)*D11'*D12;