Re: matrices
- To: mathgroup at yoda.physics.unc.edu
- Subject: Re: matrices
- From: Steven M. Christensen <stevec at yoda.physics.unc.edu>
- Date: Tue, 30 Mar 93 16:45:17 EST
[With regard to multiplying matrics and scalars posted by
Cetin]
MathTensor does your problem very easily - if you don't
mind indices.
Steve C.
Loading MathTensor for UNIX . . .
========================================================
MathTensor (TM) 2.1.5 (UNIX (R)) (January 1, 1993)
by Leonard Parker and Steven M. Christensen
Copyright (c) 1991-1993 MathSolutions, Inc.
Runs with Mathematica (R) Versions 1.2, 2.0, and 2.1.
Licensed to machine sunny.
========================================================
No unit system is chosen. If you want one,
you must edit the file called Conventions.m,
or enter a command to interactively set units.
Units: {}
Sign conventions: Rmsign = 1 Rcsign = 1
MetricgSign = 1 DetgSign = -1
TensorForm turned on,
ShowTime turned off,
MetricgFlag = True.
=========================================
In[2]:= DefineTensor[A,"A",{{1,2},1}]
In[3]:= DefineTensor[B,"B",{{1,2},1}]
In[4]:= A[ua,lb] A[ub,lc] + A[ua,lb] (B[ub,lc] eps) + (B[ua,lb] eps) A[ub,lc] + (B[ua,lb] eps) (B[ub,lc] eps)
a b b a a b 2 a b
Out[4]= A A + eps A B + eps A B + eps B B
b c c b b c b c
In[5]:= Collect[%,eps]
a b 2 a b b a a b
Out[5]= A A + eps B B + eps (A B + A B )
b c b c c b b c
In[6]:= Quit