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Re: matrixcol element
On Fri, 13 Mar 1998, Richard J. Fateman wrote:
> you mean matrixcol(m,c) = matrixrow(transpose(m),c) or some such.
> If we had an appropriate object-oriented approach, then optional
> methods could trade off between storage /access / time . Frankly,
> I never thought of any of the openmath / math-sgml etc as dictating
> either storage formats, access efficiency, etc. Just an inefficient
> textual suggestion of what people might plausibly interpret the
> same way in spite of having different basic assumptions.
I often think of the columns of a matrix to be more important than the
rows. Mainly this is due to the fact that e_i maps to the ith column of a
matrix. So when I construct a matrix I likely know its column vectors
and not its row vectors.
This is refected when you see matrices written as:
_ _
| | | | |
A = | V_1 | V_2 | ... | V_n |
|_ | | | _|
which is far more common that a row vector form.
This is where my thoughts of matrices alternately being defined by columns
comes from. I don't know if there is time to put this idea into version
1.0 of MathML
--
Russell O'Connor roconnor@uwaterloo.ca
<URL:http://www.undergrad.math.uwaterloo.ca/%7Eroconnor/>
"And truth irreversibly destroys the meaning of its own message"
-- Anindita Dutta, "The Paradox of Truth, the Truth of Entropy"