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+++ b/liboctave/fDiagMatrix.h
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+/*
+
+Copyright (C) 1994, 1995, 1996, 1997, 2000, 2002, 2004, 2005, 2006,
+              2007 John W. Eaton
+
+This file is part of Octave.
+
+Octave is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 3 of the License, or (at your
+option) any later version.
+
+Octave is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with Octave; see the file COPYING.  If not, see
+<http://www.gnu.org/licenses/>.
+
+*/
+
+#if !defined (octave_FloatDiagMatrix_h)
+#define octave_FloatDiagMatrix_h 1
+
+#include "MDiagArray2.h"
+
+#include "fRowVector.h"
+#include "fColVector.h"
+
+#include "mx-defs.h"
+
+class
+OCTAVE_API
+FloatDiagMatrix : public MDiagArray2<float>
+{
+friend class FloatSVD;
+friend class FloatComplexSVD;
+
+public:
+
+  FloatDiagMatrix (void) : MDiagArray2<float> () { }
+
+  FloatDiagMatrix (octave_idx_type r, octave_idx_type c) : MDiagArray2<float> (r, c) { }
+
+  FloatDiagMatrix (octave_idx_type r, octave_idx_type c, float val) : MDiagArray2<float> (r, c, val) { }
+
+  FloatDiagMatrix (const FloatDiagMatrix& a) : MDiagArray2<float> (a) { }
+
+  FloatDiagMatrix (const MDiagArray2<float>& a) : MDiagArray2<float> (a) { }
+
+  explicit FloatDiagMatrix (const FloatRowVector& a) : MDiagArray2<float> (a) { }
+
+  explicit FloatDiagMatrix (const FloatColumnVector& a) : MDiagArray2<float> (a) { }
+
+  FloatDiagMatrix& operator = (const FloatDiagMatrix& a)
+    {
+      MDiagArray2<float>::operator = (a);
+      return *this;
+    }
+
+  bool operator == (const FloatDiagMatrix& a) const;
+  bool operator != (const FloatDiagMatrix& a) const;
+
+  FloatDiagMatrix& fill (float val);
+  FloatDiagMatrix& fill (float val, octave_idx_type beg, octave_idx_type end);
+  FloatDiagMatrix& fill (const FloatColumnVector& a);
+  FloatDiagMatrix& fill (const FloatRowVector& a);
+  FloatDiagMatrix& fill (const FloatColumnVector& a, octave_idx_type beg);
+  FloatDiagMatrix& fill (const FloatRowVector& a, octave_idx_type beg);
+
+  FloatDiagMatrix transpose (void) const { return MDiagArray2<float>::transpose(); }
+
+  friend OCTAVE_API FloatDiagMatrix real (const FloatComplexDiagMatrix& a);
+  friend OCTAVE_API FloatDiagMatrix imag (const FloatComplexDiagMatrix& a);
+
+  // resize is the destructive analog for this one
+
+  FloatMatrix extract (octave_idx_type r1, octave_idx_type c1, octave_idx_type r2, octave_idx_type c2) const;
+
+  // extract row or column i.
+
+  FloatRowVector row (octave_idx_type i) const;
+  FloatRowVector row (char *s) const;
+
+  FloatColumnVector column (octave_idx_type i) const;
+  FloatColumnVector column (char *s) const;
+
+  FloatDiagMatrix inverse (void) const;
+  FloatDiagMatrix inverse (int& info) const;
+
+  // other operations
+
+  FloatColumnVector diag (octave_idx_type k = 0) const;
+
+  // i/o
+
+  friend OCTAVE_API std::ostream& operator << (std::ostream& os, const FloatDiagMatrix& a);
+
+private:
+
+  FloatDiagMatrix (float *d, octave_idx_type nr, octave_idx_type nc) : MDiagArray2<float> (d, nr, nc) { }
+};
+
+// diagonal matrix by diagonal matrix -> diagonal matrix operations
+
+FloatDiagMatrix
+operator * (const FloatDiagMatrix& a, const FloatDiagMatrix& b);
+
+MDIAGARRAY2_FORWARD_DEFS (MDiagArray2, FloatDiagMatrix, float)
+
+#endif
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; End: ***
+*/