From help-octave-request at bevo dot che dot wisc dot edu Tue Feb 11 10:28:07 2003
Subject: Re: polyfit weirdness
From: Scott Lamb <slamb at slamb dot org>
To: Etienne Grossmann <etienne at isr dot isr dot ist dot utl dot pt>
Cc: help-octave at bevo dot che dot wisc dot edu
Date: Tue, 11 Feb 2003 10:25:12 -0600

Etienne Grossmann wrote:
>      A problem with order of magnitude of f1 and floating-point
>      limitations?
> 
> 
> octave:63> f1 /= 1e14;
> octave:64>      [p1,cv1] = polyfit(f1,v1,1)'
> p1 =
> 
>    0.41679
>   -1.49481
> 
> cv1 =
> 
>   0.66528  0.79417  1.37189  1.59260  1.92606
> 
>      Is that more like what you expected?

Yes, it is, thanks.

I'm a little disappointed Octave has this problem; I'd assumed it would 
be using gmp or something for arbitrary precision. Oh well.

Thanks,
Scott Lamb



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