Re: matrix of coefficients?
- To: mathgroup at christensen.cybernetics.net
- Subject: Re: matrix of coefficients?
- From: Richard Mercer <richard at rmercer.wright.edu>
- Date: Tue, 25 Oct 1994 08:29:08 -0400
> Dear mathgroupers:
>
> If varsN = a list of N variables, and if exprsN = a list
> of of N expressions, each one linear in the variables of
> varsN,
>
> Is there some operator (that I haven't found yet), or
> some clever way to use a nonobvious operator, to get the
> matrix of coefficients?
>
> I'm doing it, but it is not a pretty sight. I just have
> a feeling there must be some neat way to do this very
> commonly needed operation. Thanks- Martin McClain,
> Chemistry, Wayne State University, Detroit
>
I agree.
What you want is
Outer[Coefficient,exprsN,varsN]
In[11]:=
exprsN = {3x + 4y + 5z, 6x + 7y + 8z, 9x + 10y + 11z};
varsN = {x,y,z};
Outer[Coefficient,exprsN,varsN]
Out[13]=
{{3, 4, 5}, {6, 7, 8}, {9, 10, 11}}
Try it!
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Richard Mercer 513-873-2191 office
Department of Mathematics and Statistics 513-873-2785 message
Wright State University 513-429-2179 fax
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richard at rmercer.wright.edu or rmercer at desire.wright.edu
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