[Toon-members] TooN GR_SVD.h

[Georg Klein]

CVSROOT:        /sources/toon
Module name:    TooN
Changes by:     Georg Klein <georgklein>        09/08/25 19:21:44

Modified files:
        .              : GR_SVD.h 

Log message:
        Added reorder() method which re-arranges components so that singular 
values
        are in descending order.

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/TooN/GR_SVD.h?cvsroot=toon&r1=1.2&r2=1.3

Patches:
Index: GR_SVD.h
===================================================================
RCS file: /sources/toon/TooN/GR_SVD.h,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -b -r1.2 -r1.3
--- GR_SVD.h    25 Aug 2009 16:09:53 -0000      1.2
+++ GR_SVD.h    25 Aug 2009 19:21:43 -0000      1.3
@@ -32,6 +32,8 @@
 
 #include <TooN/TooN.h>
 #include <cmath>
+#include <vector>
+#include <algorithm>
 
 namespace TooN
 {
@@ -117,6 +119,8 @@
       return diagmult(get_V(),inv_diag) * get_U().T();
     }
     
+    // Reorder the components so the singular values are in descending order
+    void reorder();
     
   protected:
     void Bidiagonalize();
@@ -484,5 +488,30 @@
     return nMin;
   }
 
+  template<int M, int N, class Precision, bool WANT_U, bool WANT_V>
+  void GR_SVD<M,N,Precision,WANT_U,WANT_V>::reorder()
+  {
+    Matrix<M, N, Precision> mU_copy = mU;
+    Matrix<N, N, Precision> mV_copy = mV;
+    
+    std::vector<std::pair<Precision, unsigned int> > vSort;
+    vSort.reserve(N);
+    for(unsigned int i=0; i<N; ++i)
+      vSort.push_back(std::make_pair(-vDiagonal[i], i));
+    std::sort(vSort.begin(), vSort.end());
+    for(unsigned int i=0; i<N; ++i)
+      mU.T()[i] = mU_copy.T()[vSort[i].second];
+    for(unsigned int i=0; i<N; ++i)
+      mV.T()[i] = mV_copy.T()[vSort[i].second];
+    for(unsigned int i=0; i<N; ++i)
+      vDiagonal[i] = -vSort[i].first;
+  }
+
 }
 #endif
+
+
+
+
+
+