Raymond Toy wrote:
>
> >>>>> "James" == James Amundson <amundson@fnal.gov> writes:
>
> James> Previously, I could do this:
>
> James> (C1) %j[1](sqrt(x));
> James> (D1) %J (SQRT(x))
> James> 1
>
> James> Now, I get this:
>
> James> (C1) %j[1](sqrt(x));
>
> James> Is x positive, negative, or zero?
>
> James> This bug has to be fixed. I see you updated to tests to work around the
> James> bug. Please roll back those changes. I haven't found the source of the
> James> bug yet, but the above information should be a good lead.
>
> Yes. I'll fix this asap.
>
> But perhaps my choice of using adding simplifiers to %j was wrong.
> Maybe I should have left them for bessel_j, as Macsyma seems to call
> it? I didn't do that because I didn't want to duplicate whatever was
> done for %j and friends.
>
> >> For rtest14.mac, test 3 has the wrong value for bessel(2,3), which is
> >> purely real, not complex.
BesselJ[2,3.0000000000000000] in Mathematica is
0.4860912605858910769078310941149840346217631456341594 approximately.
>
> James> Right. The only reason I hadn't updated that number is that I wanted to
> James> get verify the number through a third party. It is obvious that some of
> James> the tests in the special function section are checking against values
> James> that are incorrect past single-precision. I would love to have a
> James> volunteer audit all the special function numerical tests. Comparison
> James> with a third party is really necessary.
>
> FWIW, matlab says
>
> 0.12894324947440
>
> whereas we say
>
> 0.1289432494744021
>
> If you really want an answer, I'll probably have to hit the library to
> find some more accurate tables.
>
> >> Don't know about test 16. I suspect this
> >> might be caused by my change to make %j[1/2](x) expand to elementary
> >> functions.
>
> James> Is it related to the bug I described above?
>
> I modified the bessel routines not to expand these unless besselexpand
> is true. Test 16 passes now.
>
> Ray
> _______________________________________________
> Maxima mailing list
> Maxima@www.math.utexas.edu
> http://www.math.utexas.edu/mailman/listinfo/maxima