Re: No Invert Functions?

Joseph Dale <[email protected]>
Newsgroups gmane.lisp.matlisp.user
Message-ID <[email protected]>
Michael A. Koerber wrote:
>>I've just installed matlisp from the latest CVS at sourceforge. From 
>>looking at the online help and reading some of the source, it looks to 
>>me like none of the wrappers around matrix inversion functions (for 
>>example, DGETRI and ZGETRI in LAPACK) have been implemented. Is there 
>>any particular reason for this omission, or is it just lack of time? Or 
>>am I totally missing something?
> 
> 
> Joe,
> 
>   I don't see such a wrapper either.  However, matrix inversion is
> currently performed with ZGESV by calling the MATLISP function M/ with
> a single argument.  So if you just need the inverse of A use (M/ A).
> Of course, if its ?GETRI specifically, a wrapper will be needed.
> 

Thanks Michael and Tunc,

M/ should be sufficient for me. However, there appears to be a bug/typo 
in the documentation:


* (help m/)

In package MATLISP, the function M/
===================================

   Syntax
   ======
   (M/ a [b])

   Purpose
   =======

   Equivalent to inv(A) * B, but far more efficient and accurate.
   If A is not given, the inverse of B is returned.

   A is an NxN square matrix and B is NxM.

   B may be a scalar in which case M/ is equivalent to M./

   See M/!, M./, M./!, GESV


It seems that the line "If A is not given, the inverse of B is 
returned." should read "If B is not given, the inverse of A is returned."


Joe
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