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Discussion: new operators for numerical computation

Robin Becker robin at jessikat.fsnet.co.uk
Mon Jul 24 07:28:11 EDT 2000 
In article <m3n1j73iuz.fsf at chinon.cnrs-orleans.fr>, Konrad Hinsen
<hinsen at cnrs-orleans.fr> writes
....
>What are "Greg's indexing rules"? Inner and outer product are entirely
>different operations in my mind, although in principle the inner
>product can be thought of as an outer product followed by a summation.
>I think that implementation issues also call for separate operators;
>using indexing tricks might be difficult for sparse matrices, for
>example.
>
....
outer products (of vectors at least) are inner products with the second
vector being transposed. There is of course a general tensor notation,
but as Python lacks the distinction between sub/super scripts that's a
bit difficult.

One thing I personally find very strange is that very few in this thread
seem to want to make the default multiplication operation * into the
default matrix multiply. I suppose early language designers have decided
this for all time so all choose the unusual element wise operation.
-- 
Robin Becker
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