r9068 - /1.3/maths_fns/kronecker_product.py -- June 08, 2009 - 16:21

Author: bugman
Date: Mon Jun  8 16:21:38 2009
New Revision: 9068

URL: http://svn.gna.org/viewcvs/relax?rev=9068&view=rev
Log:
Added a function for calculating the Kronecker product.


Added:
    1.3/maths_fns/kronecker_product.py

Added: 1.3/maths_fns/kronecker_product.py
URL: 
http://svn.gna.org/viewcvs/relax/1.3/maths_fns/kronecker_product.py?rev=9068&view=auto
==============================================================================
--- 1.3/maths_fns/kronecker_product.py (added)
+++ 1.3/maths_fns/kronecker_product.py Mon Jun  8 16:21:38 2009
@@ -1,0 +1,22 @@
+from numpy import concatenate, outer
+
+
+def kron_prod(A, B):
+    """Calculate the Kronecker product of the matrices A and B.
+
+    @param A:   ixj matrix.
+    @type A:    rank-2 numpy array
+    @param B:   kxl matrix.
+    @type B:    rank-2 numpy array
+    @return:    The Kronecker product.
+    @rtype:     ikxjl rank-2 numpy array
+    """
+
+    # The outer product.
+    C = outer(A, B)
+
+    # Redefine the shape.
+    C.shape = A.shape + B.shape
+
+    # Generate and return the Kronecker product matrix.
+    return concatenate(concatenate(C, axis=1), axis=1)