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From: sam@kalessin.jpl.nasa.gov (Sam Sirlin)
Newsgroups: comp.lang.apl
Subject: Re: Determinant
Message-ID: <1991May21.161641.18112@jato.jpl.nasa.gov>
Date: 21 May 91 16:16:41 GMT
References: <1991May19.053021.7840@yrloc.ipsa.reuter.COM>
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Reply-To: sam@kalessin.jpl.nasa.gov (Sam Sirlin)
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In article <1991May19.053021.7840@yrloc.ipsa.reuter.COM>, hui@yrloc.ipsa.reuter.COM (Roger Hui) writes:
|> The determinant has been implemented in J this week.  The determinant has
|> rank 2 (applies to matrices), and is recursively defined by expansion
|> by minors along column 0:
|>  

This sounds interesting, but if I was given a matrix and told to take its
determinant, I would use LU or SV decomposition if the matrix was above 
about 6th order. Isn't the minor calculation ill conditioned? If so then
isn't a built in determinant using minors missleading to naive programmers?

-- 
Sam Sirlin
Jet Propulsion Laboratory         sam@kalessin.jpl.nasa.gov