Igor Schein on Mon, 2 Oct 2000 10:48:56 -0400


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Re: eigen() strikes again 

On Sun, Oct 01, 2000 at 11:00:03PM -0400, Ilya Zakharevich wrote:
> With a week-old version:
> 
>     ? mateigen([1,2;3,4])
>       ***   precision too low in eigen.

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% sed -n 14,22p TODO 
***************************   BUGS (general)     ****************************
Unless specified otherwise, examples assume 32bit machine and default precision 

5  setrand(5);thueinit(x^3 + x^2 - 43690*x - 3529208)
   ***   non positive argument in mplog. \\ precision problem

4  gcmp/gegal not transitive: [] == 0, [0] == 0, but [0] != []

4  mateigen([1,1;1,2]) won't succeed \\ works if precision is increased	<--
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So it's a known problem.

Igor