[PYTHON MATRIX-SIG] linear algebra

Jim Hugunin hugunin@mit.edu
Mon, 19 Aug 1996 09:38:35 -0400


I'm finally having some good success at putting together a standard
library for NumPy.  There will be easy to compile, small C versions of
all the necessary Lapack and Blas routines available so that anybody
with a C compiler can use the standard lib.  Now I have a question for
those people out there who use linear algebra more than I do.

All of the current interface routines (from LinAlg.py) do the following:

return transpose(lapackfunction(transpose(input_matrix)))

Should these two transpositions be there?  This is obviously related to
the different index order between NumPy and FORTRAN.  Still, I've always
personally considered it a superficial difference that is best ignored.

If I remember by Linear Algebra correctly
transpose(inverse(transpose(m))) == inverse(m).

However, I very rarely use any linear algebra functions in my code so
I'm not the right person to be making that decision.  Opinions?

-Jim

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