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Re: [Q] symbolic SVD?

• To: mathgroup at smc.vnet.net
• Subject: [mg26840] Re: [Q] symbolic SVD?
• From: "Paul Lutus" <nospam at nosite.com>
• Date: Thu, 25 Jan 2001 01:13:19 -0500 (EST)
• References: <94m9jq$3o7@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

"James" <research at proton.csl.uiuc.edu> wrote in message
news:94m9jq$3o7 at smc.vnet.net...
>
>
> Sorry about reposting.
> I've not received any reply yet,
> and I tried several ways, but I couldn't get a clue, either.
> So if anyone can help, that would be appreciated.
>
> -------------------------------------------------------------
>
> I've used 'symbolic' calculation in mathematica in many ways,
> but this time,
> I wonder if mathematica can solve symbolic matrix operation.
> Specifically,
>
>    m = {{a, b},
>         {c, d},
>         {e, f}}
>
>    SingluarValues[m]
>
> returns
>
>   SingularValues::"svdf": "SingularValues has received a matrix
>           with infinite precision."
>
> (a,b,c,d,e,f are all symbolics.)
> I need to do several symbolic matrix operations such as SingularValues.
> Is there any way to do that?

The values in the matrix must not be undefined variables, or variables with
infinite precision.

Try:

m = {{1.,2.},
     {3.,4.},
     {5.,6.}}

SingularValues[m]


"SingularValues[m] gives the singular value decomposition for a numerical
matrix m. "

Note the word "numerical."

--
Paul Lutus
www.arachnoid.com