Albert van der Horst albert at spenarnc.xs4all.nl
Sat May 10 12:39:02 EDT 2014

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In article <874n0xvd85.fsf at dpt-info.u-strasbg.fr>,
Alain Ketterlin  <alain at dpt-info.u-strasbg.fr> wrote:
>albert at spenarnc.xs4all.nl (Albert van der Horst) writes:
>
>[...]
>> Now on some matrices the assert triggers, meaning that nom is zero.
>> How can that ever happen? mon start out as 1. and gets multiplied
>
>[several times]
>
>> with a number that is asserted to be not zero.
>
>Finite precision. Try: 1.*1e-162*1e-162. Equals zero.
>
>-- Alain.

Thanks you Alan and all others to point this out.
That was indeed the problem. Somehow I expected that floating
underflow would raise an exception, so I had a blind spot there.

Groetjes Albert
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert at spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst

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