Re: Matrix Dot Product

*To*: mathgroup at smc.vnet.net*Subject*: [mg52200] Re: [mg52159] Matrix Dot Product*From*: yehuda ben-shimol <benshimo at bgu.ac.il>*Date*: Sun, 14 Nov 2004 04:31:15 -0500 (EST)*References*: <200411130940.EAA00971@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

You have a special function for that Dot[ ] please look below In[3]:= ?Dot \!\(\* RowBox[{"\<\"a.b.c or Dot[a, b, c] gives products of vectors, matrices and \ tensors.\"\>", " ", ButtonBox[ StyleBox["More?", "SR"], ButtonData:>"Dot", Active->True, ButtonStyle->"RefGuideLink"]}]\) yehuda MacDonald, Calum (MAT) wrote: >Hi > >I was wondering if someone could please help me with a command for >calculating the dot product of two (NxN) matrices. > >For example, for two (2x2) matrices, A and B, we define the dot product >as: > >A(1,1)*B(1,1) + A(2,1)*B(2,1) + A(1,2)*B(1,2) + A(2,2)*B(2,2) > >i.e. we multiply corresponding entries of the matrices and sum these >values. > >It is easy to write this in a loop but for large matrices the >calculation is rather slow. > >Is there a Mathematica function that I can call that will allow me to do >this faster? > >Thanks > >Calum > > > > >

**References**:**Matrix Dot Product***From:*"MacDonald, Calum \(MAT\)" <C.A.MacDonald@gcal.ac.uk>