--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/log.cc	Wed Jul 13 02:31:31 1994 +0000
@@ -0,0 +1,264 @@
+// f-log.cc                                           -*- C++ -*-
+/*
+
+Copyright (C) 1994 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 2, 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, write to the Free
+Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "EIG.h"
+
+#include "tree-const.h"
+#include "user-prefs.h"
+#include "error.h"
+#include "gripes.h"
+#include "f-log.h"
+
+// XXX FIXME XXX -- the next two functions (and expm) should really be just
+// one...
+
+Octave_object
+matrix_log (const tree_constant& a)
+{
+  Octave_object retval (1);
+
+  tree_constant tmp = a.make_numeric ();;
+    
+  if (tmp.rows () == 0 || tmp.columns () == 0)
+    {
+      int flag = user_pref.propagate_empty_matrices;
+      if (flag != 0)
+	{
+	  if (flag < 0)
+	    gripe_empty_arg ("logm", 0);
+	  Matrix m;
+	  retval(0) = m;
+	  return retval;
+	}
+      else
+	gripe_empty_arg ("logm", 1);
+    }
+
+  switch (tmp.const_type ())
+    {
+    case tree_constant_rep::matrix_constant:
+      {
+	Matrix m = tmp.matrix_value ();
+
+	int nr = m.rows ();
+	int nc = m.columns ();
+
+	if (nr == 0 || nc == 0 || nr != nc)
+	  gripe_square_matrix_required ("logm");
+	else
+	  {
+	    EIG m_eig (m);
+	    ComplexColumnVector lambda (m_eig.eigenvalues ());
+	    ComplexMatrix Q (m_eig.eigenvectors ());
+
+	    for (int i = 0; i < nr; i++)
+	      {
+		Complex elt = lambda.elem (i);
+		if (imag (elt) == 0.0 && real (elt) > 0.0)
+		  lambda.elem (i) = log (real (elt));
+		else
+		  lambda.elem (i) = log (elt);
+	      }
+
+	    ComplexDiagMatrix D (lambda);
+	    ComplexMatrix result = Q * D * Q.inverse ();
+
+	    retval(0) = result;
+	  }
+      }
+      break;
+    case tree_constant_rep::complex_matrix_constant:
+      {
+	ComplexMatrix m = tmp.complex_matrix_value ();
+
+	int nr = m.rows ();
+	int nc = m.columns ();
+
+	if (nr == 0 || nc == 0 || nr != nc)
+	  gripe_square_matrix_required ("logm");
+	else
+	  {
+	    EIG m_eig (m);
+	    ComplexColumnVector lambda (m_eig.eigenvalues ());
+	    ComplexMatrix Q (m_eig.eigenvectors ());
+
+	    for (int i = 0; i < nr; i++)
+	      {
+		Complex elt = lambda.elem (i);
+		if (imag (elt) == 0.0 && real (elt) > 0.0)
+		  lambda.elem (i) = log (real (elt));
+		else
+		  lambda.elem (i) = log (elt);
+	      }
+
+	    ComplexDiagMatrix D (lambda);
+	    ComplexMatrix result = Q * D * Q.inverse ();
+
+	    retval(0) = result;
+	  }
+      }
+      break;
+    case tree_constant_rep::scalar_constant:
+      {
+	double d = tmp.double_value ();
+	if (d > 0.0)
+	  retval(0) = log (d);
+	else
+	  {
+	    Complex dtmp (d);
+	    retval(0) = log (dtmp);
+	  }
+      }
+      break;
+    case tree_constant_rep::complex_scalar_constant:
+      {
+	Complex c = tmp.complex_value ();
+	retval(0) = log (c);
+      }
+      break;
+    default:
+      break;
+    }
+  return retval;
+}
+
+Octave_object
+matrix_sqrt (const tree_constant& a)
+{
+  Octave_object retval (1);
+
+  tree_constant tmp = a.make_numeric ();;
+    
+  if (tmp.rows () == 0 || tmp.columns () == 0)
+    {
+      int flag = user_pref.propagate_empty_matrices;
+      if (flag != 0)
+	{
+	  if (flag < 0)
+	    gripe_empty_arg ("sqrtm", 0);
+	  Matrix m;
+	  retval(0) = m;
+	  return retval;
+	}
+      else
+	gripe_empty_arg ("sqrtm", 1);
+    }
+
+  switch (tmp.const_type ())
+    {
+    case tree_constant_rep::matrix_constant:
+      {
+	Matrix m = tmp.matrix_value ();
+
+	int nr = m.rows ();
+	int nc = m.columns ();
+
+	if (nr == 0 || nc == 0 || nr != nc)
+	  gripe_square_matrix_required ("sqrtm");
+	else
+	  {
+	    EIG m_eig (m);
+	    ComplexColumnVector lambda (m_eig.eigenvalues ());
+	    ComplexMatrix Q (m_eig.eigenvectors ());
+
+	    for (int i = 0; i < nr; i++)
+	      {
+		Complex elt = lambda.elem (i);
+		if (imag (elt) == 0.0 && real (elt) > 0.0)
+		  lambda.elem (i) = sqrt (real (elt));
+		else
+		  lambda.elem (i) = sqrt (elt);
+	      }
+
+	    ComplexDiagMatrix D (lambda);
+	    ComplexMatrix result = Q * D * Q.inverse ();
+
+	    retval(0) = result;
+	  }
+      }
+      break;
+    case tree_constant_rep::complex_matrix_constant:
+      {
+	ComplexMatrix m = tmp.complex_matrix_value ();
+
+	int nr = m.rows ();
+	int nc = m.columns ();
+
+	if (nr == 0 || nc == 0 || nr != nc)
+	  gripe_square_matrix_required ("sqrtm");
+	else
+	  {
+	    EIG m_eig (m);
+	    ComplexColumnVector lambda (m_eig.eigenvalues ());
+	    ComplexMatrix Q (m_eig.eigenvectors ());
+
+	    for (int i = 0; i < nr; i++)
+	      {
+		Complex elt = lambda.elem (i);
+		if (imag (elt) == 0.0 && real (elt) > 0.0)
+		  lambda.elem (i) = sqrt (real (elt));
+		else
+		  lambda.elem (i) = sqrt (elt);
+	      }
+
+	    ComplexDiagMatrix D (lambda);
+	    ComplexMatrix result = Q * D * Q.inverse ();
+
+	    retval(0) = result;
+	  }
+      }
+      break;
+    case tree_constant_rep::scalar_constant:
+      {
+	double d = tmp.double_value ();
+	if (d > 0.0)
+	  retval(0) = sqrt (d);
+	else
+	  {
+	    Complex dtmp (d);
+	    retval(0) = sqrt (dtmp);
+	  }
+      }
+      break;
+    case tree_constant_rep::complex_scalar_constant:
+      {
+	Complex c = tmp.complex_value ();
+	retval(0) = log (c);
+      }
+      break;
+    default:
+      break;
+    }
+  return retval;
+}
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; page-delimiter: "^/\\*" ***
+;;; End: ***
+*/