[Scipy-tickets] [SciPy] #313: Support for Kronecker sum

SciPy scipy-tickets at scipy.net
Thu Nov 23 02:16:06 CST 2006


#313: Support for Kronecker sum
--------------------------+-------------------------------------------------
 Reporter:  nils          |       Owner:  somebody
     Type:  enhancement   |      Status:  new     
 Priority:  normal        |   Milestone:          
Component:  scipy.linalg  |     Version:  devel   
 Severity:  normal        |    Keywords:          
--------------------------+-------------------------------------------------
 A definition of the Kronecker sum is given in the recent book by Alan J.
 Laub
 '''Matrix Analysis for Scientists and Engineers''' SIAM (2005).
 {{{
 def kronsum(a,b):
     """kronecker sum of a and b

     Kronecker sum of two matrices is a sum
     of two Kronecker products kron(I_m,a)+kron(b,I_n)

     Inputs:

       a -- An n x n matrix.
       b -- An m x m matrix
     """
     a1 = asarray_chkfinite(a)
     if len(a1.shape) != 2 or a1.shape[0] != a1.shape[1]:
         raise ValueError, 'expected square matrix'
     b1 = asarray_chkfinite(b)
     if len(b1.shape) != 2 or b1.shape[0] != b1.shape[1]:
         raise ValueError, 'expected square matrix'

     return
 linalg.kron(identity(b1.shape[0]),a)+linalg.kron(b,identity(a1.shape[0]))
 }}}

-- 
Ticket URL: <http://projects.scipy.org/scipy/scipy/ticket/313>
SciPy <http://www.scipy.org/>
SciPy is open-source software for mathematics, science, and engineering.


More information about the Scipy-tickets mailing list