Re: Rambling on numbers in Haskell

[Jan Skibinski]

        Hi Jon:

> 
> whoops!  I meant to say 
> sqrt :: (Numeric n,  Numeric f) => n -> f
> 
> or something - the important bit was that the result type shouldn't be
> constrained to be the same as the argument, because while sqrt int is
> meaningful it doesn't usually give an int result.  What you get back
> should depend on what you use it for.

        OK, I agree here. Mine was just some quick example, and
        I do not promote squishing everything into one type.

        As long as my other example with eigenvalues works for me,
        that is: as long as I can hope for a vector of reals
        OR complex, I am satisfied. But I definitely do not want
        an error, because I know up front that some solution exists
        - be it real or complex. Sometimes I can predict which one,
        but often I cannot.

        Jan