Karim Belabas on Wed, 25 Sep 2013 16:20:17 +0200

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Re: Zeta() changes in recent versions?

* Andrew Walker [2013-09-24 06:52]:
> I'm just wondering what changes have been made with zeta() evaluation between the 2.5.X series and the 2.6.X series.
> For multiple evaluations (eg series) it can be slower which makes me think some of its reuse behavior has been removed or is broken.

Good catch ! This affects 2.6.0 and 2.6.1 and is due to a typo I introduced
when changing the cache model for Bernoulli numbers [ to compute and store
them individually, either as exact fractions or as floating point numbers, with
their own individual accuracies; instead of as a large homogeneous chunk that
had to be discarded entirely whenever a single component had to be updated ].

Due to the typo, Bernoulli numbers were no longer cached "automagically".
And Euler-Maclaurin became prohibitive...

This bug is fixed in

  commit 642e04af2e489bc4e1c222357a424bd8ec20cca3
  Author: Karim Belabas <Karim.Belabas@math.u-bordeaux1.fr>
  Date:   Wed Sep 25 15:56:56 2013 +0200


Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
Universite Bordeaux 1          Fax: (+33) (0)5 40 00 69 50
351, cours de la Liberation    http://www.math.u-bordeaux1.fr/~kbelabas/
F-33405 Talence (France)       http://pari.math.u-bordeaux1.fr/  [PARI/GP]