Re: matrix algebra

*To*: mathgroup at smc.vnet.net*Subject*: [mg3700] Re: matrix algebra*From*: Harald Berndt <haraldb at nature.berkeley.edu>*Date*: Mon, 8 Apr 1996 02:06:06 -0400*Organization*: University of California Forest Prodcts Lab*Sender*: owner-wri-mathgroup at wolfram.com

Juan Garcia Velo wrote: > > Does anybody know of a package of functions and operators that can deal > with partitioned matrices? Example: > mat_a = [ a b ] mat_b = [ d c ] > [ c d ] [ b a ] > where a, b, c, d are matrices (although not necessarily defined) of > appropriate dimensions. Then I can do MULT[mat_a,mat_b] and get > mat_c = [ a d + b b a c + b a ] > [ c d + d b c c + d a ] > without any attempt of changing the order in the products defining the > elements of mat_c, because they are matrices, obviously. > > Juan Would it be sufficient for your needs to just use the generalization of the Dot product, Inner[f, list1, list2, g], with f=Dot and g=Plus? You won't have any dimension checking etc. and will need to write out explicitly what you want each time, but it will do what you want, I believe. -- ______________________________________________________________________ Harald Berndt, University of California Research Specialist Forest Products Laboratory Phone: 510-215-4224 FAX: 510-215-4299 ==== [MESSAGE SEPARATOR] ====