Dieter Kaiser wrote:
> Hello Ray,
>
> It seems to me that I am a bit tired. Again I was too fast. I did the check for
> conjugate values with different algorithm and not with conjugate values.
>
> Now I arrived at this routine:
>
> (defun expintegral-ei (z)
> (+
> (- (expintegral-e 1 (- z)))
> ; (- (* 0.5 (- (log z) (log (/ 1 z)))) (log (- z)))
> (cond
> ((> (imagpart z) 0)
> ;; Positive imaginary part. Add phase %i*%pi.
> (complex 0 (float pi)))
> ((< (imagpart z) 0)
> ;; Negative imaginary part. Add phase -%i*%pi.
> (complex 0 (- (float pi))))
> ((> (realpart z) 0)
> ;; Positive real value. Add phase -%i*pi.
> (complex 0 (- (float pi))))
> ;; Negative real value. No phase factor.
> (t 0))))
>
> Again the results I obtained with GCL:
I've checked this version in now, since all the exponential integral
tests pass on cmucl.
There is one issue with ecl where 169 fails for -1+14*%i, but it is due
to a bug in ecl. This bug is supposed to be fixed in the CVS version of
yesterday or so, so I'm not going to do fix that in maxima.
Yay! Now there are a couple more issues with cmucl and rtest_gamma,
where tests 264, 311, 313, and 319 fail. Looks like the accuracy is a
bit off. Since all other Lisps (clisp, gcl, ecl), I will blame cmucl
for this. I need to look into this issue a bit more to see what the
actual problem is.
Ray