# [PYTHON MATRIX-SIG] linear algebra

**Konrad HINSEN
**
hinsenk@ere.umontreal.ca

*Mon, 19 Aug 1996 12:42:04 -0400*

>* 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).
*
True for inversion, but for little else, except in the special case of
symmetric matrices.
Personally I think it is important to work with the "right" index
order that everyone is used to. Python users should not have to know
anything about implementation details.
Besides, if I understand everything correctly, transposition should
cost almost nothing, right?
Konrad.
-------------------------------------------------------------------------------
Konrad Hinsen | E-Mail: hinsenk@ere.umontreal.ca
Departement de chimie | Tel.: +1-514-343-6111 ext. 3953
Universite de Montreal | Fax: +1-514-343-7586
C.P. 6128, succ. Centre-Ville | Deutsch/Esperanto/English/Nederlands/
Montreal (QC) H3C 3J7 | Francais (phase experimentale)
-------------------------------------------------------------------------------
=================
MATRIX-SIG - SIG on Matrix Math for Python
send messages to: matrix-sig@python.org
administrivia to: matrix-sig-request@python.org
=================