Mercurial > hg > octave-nkf

changeset 13748:77857d6fe074

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Allow more than two input arguments for the kron function, plus some cleanup. Add two new tests for new calling form. (ALL_TYPES): Remove unused macro. (dispatch_kron): Refactor kron type dispatch logic into this function. (Fkron): Update docstring and successively call new dispatch_kron function.
author Jordi Gutiérrez Hermoso <jordigh@octave.org>
date Mon, 24 Oct 2011 18:06:04 -0700
parents e8564e8b0043
children 62d1f56b0be7
files src/DLD-FUNCTIONS/kron.cc
diffstat 1 files changed, 91 insertions(+), 64 deletions(-) [+]
line wrap: on
line diff
--- a/src/DLD-FUNCTIONS/kron.cc
+++ b/src/DLD-FUNCTIONS/kron.cc
@@ -172,12 +172,77 @@
   return octave_value (kron (am, bm));
 }
 
-#define ALL_TYPES(AMT, BMT) \
-  } while (0) \
+octave_value
+dispatch_kron (const octave_value& a, const octave_value& b)
+{
+  octave_value retval;
+  if (a.is_perm_matrix () && b.is_perm_matrix ())
+    retval = do_kron<PermMatrix, PermMatrix> (a, b);
+  else if (a.is_diag_matrix ())
+    {
+      if (b.is_diag_matrix () && a.rows () == a.columns ()
+          && b.rows () == b.columns ())
+        {
+          octave_value_list tmp;
+          tmp(0) = a.diag ();
+          tmp(1) = b.diag ();
+          tmp = dispatch_kron (tmp, 1);
+          if (tmp.length () == 1)
+            retval = tmp(0).diag ();
+        }
+      else if (a.is_single_type () || b.is_single_type ())
+        {
+          if (a.is_complex_type ())
+            retval = do_kron<FloatComplexDiagMatrix, FloatComplexMatrix> (a, b);
+          else if (b.is_complex_type ())
+            retval = do_kron<FloatDiagMatrix, FloatComplexMatrix> (a, b);
+          else
+            retval = do_kron<FloatDiagMatrix, FloatMatrix> (a, b);
+        }
+      else
+        {
+          if (a.is_complex_type ())
+            retval = do_kron<ComplexDiagMatrix, ComplexMatrix> (a, b);
+          else if (b.is_complex_type ())
+            retval = do_kron<DiagMatrix, ComplexMatrix> (a, b);
+          else
+            retval = do_kron<DiagMatrix, Matrix> (a, b);
+        }
+    }
+  else if (a.is_sparse_type () || b.is_sparse_type ())
+    {
+      if (a.is_complex_type () || b.is_complex_type ())
+        retval = do_kron<SparseComplexMatrix, SparseComplexMatrix> (a, b);
+      else
+        retval = do_kron<SparseMatrix, SparseMatrix> (a, b);
+    }
+  else if (a.is_single_type () || b.is_single_type ())
+    {
+      if (a.is_complex_type ())
+        retval = do_kron<FloatComplexMatrix, FloatComplexMatrix> (a, b);
+      else if (b.is_complex_type ())
+        retval = do_kron<FloatMatrix, FloatComplexMatrix> (a, b);
+      else
+        retval = do_kron<FloatMatrix, FloatMatrix> (a, b);
+    }
+  else
+    {
+      if (a.is_complex_type ())
+        retval = do_kron<ComplexMatrix, ComplexMatrix> (a, b);
+      else if (b.is_complex_type ())
+        retval = do_kron<Matrix, ComplexMatrix> (a, b);
+      else
+        retval = do_kron<Matrix, Matrix> (a, b);
+    }
+  return retval;
+}
+
 
 DEFUN_DLD (kron, args, , "-*- texinfo -*-\n\
 @deftypefn {Loadable Function} {} kron (@var{A}, @var{B})\n\
-Form the Kronecker product of two matrices, defined block by block as\n\
+@deftypefnx {Loadable Function} {} kron (@var{A1}, @var{A2}, @dots{})\n\
+Form the Kronecker product of two or more matrices, defined block by \n\
+block as\n\
 \n\
 @example\n\
 x = [a(i, j) b]\n\
@@ -193,86 +258,48 @@
           1  2  3  4\n\
 @end group\n\
 @end example\n\
+\n\
+If there are more than two input arguments @var{A1}, @var{A2}, @dots{}, \n\
+@var{An} the Kronecker product is computed as\n\
+\n\
+@example\n\
+kron (kron (@var{A1}, @var{A2}), @dots{}, @var{An})\n\
+@end example\n\
+\n\
+@noindent\n\
+Since the Kronecker product is associative, this is well-defined.\n\
 @end deftypefn")
 {
   octave_value retval;
 
   int nargin = args.length ();
 
-  if (nargin == 2)
+  if (nargin >= 2)
     {
       octave_value a = args(0), b = args(1);
-      if (a.is_perm_matrix () && b.is_perm_matrix ())
-        retval = do_kron<PermMatrix, PermMatrix> (a, b);
-      else if (a.is_diag_matrix ())
-        {
-          if (b.is_diag_matrix () && a.rows () == a.columns ()
-              && b.rows () == b.columns ())
-            {
-              octave_value_list tmp;
-              tmp(0) = a.diag ();
-              tmp(1) = b.diag ();
-              tmp = Fkron (tmp, 1);
-              if (tmp.length () == 1)
-                retval = tmp(0).diag ();
-            }
-          else if (a.is_single_type () || b.is_single_type ())
-            {
-              if (a.is_complex_type ())
-                return do_kron<FloatComplexDiagMatrix, FloatComplexMatrix> (a, b);
-              else if (b.is_complex_type ())
-                return do_kron<FloatDiagMatrix, FloatComplexMatrix> (a, b);
-              else
-                return do_kron<FloatDiagMatrix, FloatMatrix> (a, b);
-            }
-          else
-            {
-              if (a.is_complex_type ())
-                return do_kron<ComplexDiagMatrix, ComplexMatrix> (a, b);
-              else if (b.is_complex_type ())
-                return do_kron<DiagMatrix, ComplexMatrix> (a, b);
-              else
-                return do_kron<DiagMatrix, Matrix> (a, b);
-            }
-        }
-      else if (a.is_sparse_type () || b.is_sparse_type ())
-        {
-          if (args(0).is_complex_type () || args(1).is_complex_type ())
-            return do_kron<SparseComplexMatrix, SparseComplexMatrix> (a, b);
-          else
-            return do_kron<SparseMatrix, SparseMatrix> (a, b);
-        }
-      else if (a.is_single_type () || b.is_single_type ())
-        {
-          if (a.is_complex_type ())
-            return do_kron<FloatComplexMatrix, FloatComplexMatrix> (a, b);
-          else if (b.is_complex_type ())
-            return do_kron<FloatMatrix, FloatComplexMatrix> (a, b);
-          else
-            return do_kron<FloatMatrix, FloatMatrix> (a, b);
-        }
-      else
-        {
-          if (a.is_complex_type ())
-            return do_kron<ComplexMatrix, ComplexMatrix> (a, b);
-          else if (b.is_complex_type ())
-            return do_kron<Matrix, ComplexMatrix> (a, b);
-          else
-            return do_kron<Matrix, Matrix> (a, b);
-        }
+      retval = dispatch_kron (a, b);
+      for (octave_idx_type i = 2; i < nargin; i++)
+        retval = dispatch_kron (retval, args(i));
     }
+  else
+    print_usage ();
 
   return retval;
 }
 
+
 /*
 
 %!test
 %! x = ones(2);
 %! assert( kron (x, x), ones (4));
 
-%!test
+%!shared x, y, z
+%! x =  [1, 2];
+%! y =  [-1, -2];
 %! z =  [1,  2,  3,  4; 1,  2,  3,  4; 1,  2,  3,  4];
-%! assert( kron (1:4, ones (3, 1)), z)
+%!assert (kron (1:4, ones (3, 1)), z)
+%!assert (kron (x, y, z), kron (kron (x, y), z))
+%!assert (kron (x, y, z), kron (x, kron (y, z)))
 
 */