Maxima 5.17.1 regressions for Sage



On 12/22/08, Dieter Kaiser <drdieterkaiser at web.de> wrote:

>  Thus, I do not think that we have errors in Maxima, but Sage get unexpected
>  results for the erf function with complex arguments.
>
>  Remark: We have small realparts in the results. This is due to the limited
>  numerical accuracy of the routine.

It seems reasonable that if the result is known to be be real for all
arguments in some set of arguments, that a computed numerical
approximation should likewise be real. Can't the numerical function
just return realpart(whatever) when the argument is known to yield
a real result?

best

Robert