--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/corefcn/det.cc	Fri Jul 27 15:35:00 2012 -0700
@@ -0,0 +1,253 @@
+/*
+
+Copyright (C) 1996-2012 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/>.
+
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "DET.h"
+
+#include "defun.h"
+#include "error.h"
+#include "gripes.h"
+#include "oct-obj.h"
+#include "utils.h"
+#include "ops.h"
+
+#include "ov-re-mat.h"
+#include "ov-cx-mat.h"
+#include "ov-flt-re-mat.h"
+#include "ov-flt-cx-mat.h"
+#include "ov-re-diag.h"
+#include "ov-cx-diag.h"
+#include "ov-flt-re-diag.h"
+#include "ov-flt-cx-diag.h"
+#include "ov-perm.h"
+
+#define MAYBE_CAST(VAR, CLASS) \
+  const CLASS *VAR = arg.type_id () == CLASS::static_type_id () ? \
+   dynamic_cast<const CLASS *> (&arg.get_rep ()) : 0
+
+DEFUN (det, args, nargout,
+  "-*- texinfo -*-\n\
+@deftypefn  {Built-in Function} {} det (@var{A})\n\
+@deftypefnx {Built-in Function} {[@var{d}, @var{rcond}] =} det (@var{A})\n\
+Compute the determinant of @var{A}.\n\
+\n\
+Return an estimate of the reciprocal condition number if requested.\n\
+\n\
+Routines from @sc{lapack} are used for full matrices and code from\n\
+@sc{umfpack} is used for sparse matrices.\n\
+\n\
+The determinant should not be used to check a matrix for singularity.\n\
+For that, use any of the condition number functions: @code{cond},\n\
+@code{condest}, @code{rcond}.\n\
+@seealso{cond, condest, rcond}\n\
+@end deftypefn")
+{
+  octave_value_list retval;
+
+  int nargin = args.length ();
+
+  if (nargin != 1)
+    {
+      print_usage ();
+      return retval;
+    }
+
+  octave_value arg = args(0);
+
+  octave_idx_type nr = arg.rows ();
+  octave_idx_type nc = arg.columns ();
+
+  if (nr == 0 && nc == 0)
+    {
+      retval(0) = 1.0;
+      return retval;
+    }
+
+  int arg_is_empty = empty_arg ("det", nr, nc);
+  if (arg_is_empty < 0)
+    return retval;
+  if (arg_is_empty > 0)
+    return octave_value (Matrix (1, 1, 1.0));
+
+
+  if (nr != nc)
+    {
+      gripe_square_matrix_required ("det");
+      return retval;
+    }
+
+  bool isfloat = arg.is_single_type ();
+
+  if (arg.is_diag_matrix ())
+    {
+      if (arg.is_complex_type ())
+        {
+          if (isfloat)
+            {
+              retval(0) = arg.float_complex_diag_matrix_value ().determinant ().value ();
+              if (nargout > 1)
+                retval(1) = arg.float_complex_diag_matrix_value ().rcond ();
+            }
+          else
+            {
+              retval(0) = arg.complex_diag_matrix_value ().determinant ().value ();
+              if (nargout > 1)
+                retval(1) = arg.complex_diag_matrix_value ().rcond ();
+            }
+        }
+      else
+        {
+          if (isfloat)
+            {
+              retval(0) = arg.float_diag_matrix_value ().determinant ().value ();
+              if (nargout > 1)
+                retval(1) = arg.float_diag_matrix_value ().rcond ();
+            }
+          else
+            {
+              retval(0) = arg.diag_matrix_value ().determinant ().value ();
+              if (nargout > 1)
+                retval(1) = arg.diag_matrix_value ().rcond ();
+            }
+        }
+    }
+  else if (arg.is_perm_matrix ())
+    {
+      retval(0) = static_cast<double> (arg.perm_matrix_value ().determinant ());
+      if (nargout > 1)
+        retval(1) = 1.0;
+    }
+  else if (arg.is_single_type ())
+    {
+      if (arg.is_real_type ())
+        {
+          octave_idx_type info;
+          float rcond = 0.0;
+          // Always compute rcond, so we can detect numerically
+          // singular matrices.
+          FloatMatrix m = arg.float_matrix_value ();
+          if (! error_state)
+            {
+              MAYBE_CAST (rep, octave_float_matrix);
+              MatrixType mtype = rep ? rep -> matrix_type () : MatrixType ();
+              FloatDET det = m.determinant (mtype, info, rcond);
+              retval(1) = rcond;
+              retval(0) = info == -1 ? static_cast<float>(0.0) : det.value ();
+              if (rep) rep->matrix_type (mtype);
+            }
+        }
+      else if (arg.is_complex_type ())
+        {
+          octave_idx_type info;
+          float rcond = 0.0;
+          // Always compute rcond, so we can detect numerically
+          // singular matrices.
+          FloatComplexMatrix m = arg.float_complex_matrix_value ();
+          if (! error_state)
+            {
+              MAYBE_CAST (rep, octave_float_complex_matrix);
+              MatrixType mtype = rep ? rep -> matrix_type () : MatrixType ();
+              FloatComplexDET det = m.determinant (mtype, info, rcond);
+              retval(1) = rcond;
+              retval(0) = info == -1 ? FloatComplex (0.0) : det.value ();
+              if (rep) rep->matrix_type (mtype);
+            }
+        }
+    }
+  else
+    {
+      if (arg.is_real_type ())
+        {
+          octave_idx_type info;
+          double rcond = 0.0;
+          // Always compute rcond, so we can detect numerically
+          // singular matrices.
+          if (arg.is_sparse_type ())
+            {
+              SparseMatrix m = arg.sparse_matrix_value ();
+              if (! error_state)
+                {
+                  DET det = m.determinant (info, rcond);
+                  retval(1) = rcond;
+                  retval(0) = info == -1 ? 0.0 : det.value ();
+                }
+            }
+          else
+            {
+              Matrix m = arg.matrix_value ();
+              if (! error_state)
+                {
+                  MAYBE_CAST (rep, octave_matrix);
+                  MatrixType mtype = rep ? rep -> matrix_type () : MatrixType ();
+                  DET det = m.determinant (mtype, info, rcond);
+                  retval(1) = rcond;
+                  retval(0) = info == -1 ? 0.0 : det.value ();
+                  if (rep) rep->matrix_type (mtype);
+                }
+            }
+        }
+      else if (arg.is_complex_type ())
+        {
+          octave_idx_type info;
+          double rcond = 0.0;
+          // Always compute rcond, so we can detect numerically
+          // singular matrices.
+          if (arg.is_sparse_type ())
+            {
+              SparseComplexMatrix m = arg.sparse_complex_matrix_value ();
+              if (! error_state)
+                {
+                  ComplexDET det = m.determinant (info, rcond);
+                  retval(1) = rcond;
+                  retval(0) = info == -1 ? Complex (0.0) : det.value ();
+                }
+            }
+          else
+            {
+              ComplexMatrix m = arg.complex_matrix_value ();
+              if (! error_state)
+                {
+                  MAYBE_CAST (rep, octave_complex_matrix);
+                  MatrixType mtype = rep ? rep -> matrix_type () : MatrixType ();
+                  ComplexDET det = m.determinant (mtype, info, rcond);
+                  retval(1) = rcond;
+                  retval(0) = info == -1 ? Complex (0.0) : det.value ();
+                  if (rep) rep->matrix_type (mtype);
+                }
+            }
+        }
+      else
+        gripe_wrong_type_arg ("det", arg);
+    }
+  return retval;
+}
+
+/*
+%!assert (det ([1, 2; 3, 4]), -2, 10*eps)
+%!assert (det (single ([1, 2; 3, 4])), single (-2), 10*eps ("single"))
+%!error det ()
+%!error det (1, 2)
+%!error <argument must be a square matrix> det ([1, 2; 3, 4; 5, 6])
+*/