Is there a mathematical matrix class?

[dale.amon]

I am virtually certain the answer is no, and NSMatrix is
certainly not it as it's aimed at the GUI. I have a need for
something that allows me to have a 2D sparse array which has methods
like 'transpose', horizontal and vertical reflection, column and
row operations for swapping, inserting and deleting; swapping
the contents of any two locations, etc.

It would just be incredibly useful, so much so that if it 
does not exist, some day I will have to write one. However,
I'd rather not... I'm hoping someone is going to tell me
that Class XYZ, which says nothing about Matrices, actually
is one...

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|  Dale Amon         Immortal Data          |
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| amon@vnl.com    "Data Systems for Deep Space and Time"  |
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