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MathGroup Archive 2007

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summation is equivalent to dot product??

  • To: mathgroup at smc.vnet.net
  • Subject: [mg74742] summation is equivalent to dot product??
  • From: "learner" <freephys at gmail.com>
  • Date: Tue, 3 Apr 2007 00:28:26 -0400 (EDT)

Hi, Mathematicers,
Comparing the caluclations done by summation  and dot product of the
matrix, it turns out that they are different, which i initially
thought to be equal. what is the
equivalent summation form for the dot product??

In[29]:=
F[p_,q_,r_,s_]:=p+2q+r-s;

In[31]:=
MatF=Table[F[p,q,r,s],{p,4},{q,4},{r,4},{s,4}];

In[32]:=
c={1,2.1,3,4};

In[37]:=
c=2EMatF.c//MatrixForm

 sumf[
    p_, q_] := =E2=88=91r=E2=88=91s F[p, q, r, s]*c[[r]] c[[s]];

In[41]:=
Table[sumf[p,q],{p,4},{q,4}]//MatrixForm



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