Michel Talon wrote:
>
>
> This is a very serious problem. In Mathematica you can ask to do all
> computations with 100 digits, it takes some time but it works. For example
> i had to compute the eigenvalues of a 51x51 matrix (in fact for the
> Jaynes-Cummings model, interaction of one photon mode and one spin, for a
> spin 25) and the results were totally wrong until i computed with 100
> digits.
>
In Maxima, the use of bigfloats is not as completely integrated as in
Mathematica.
Particular routines that were programmed in ordinary floating-point
arithmetic are fairly common.
Some are extended to bigfloats, like +, *, /, cos, sin, exp, log, but
not everything is done.
To do polynomial zero-finding with bigfloats you (or algsys) need (at
the moment) to call a different routine.
RJF