Le 12/03/2015 17:03, Marc Mezzarobba a écrit :
Bruno Grenet wrote:
My questions: Is my understanding correct? If not, what are supposed
these arguments to be for? And if I understand correctly, is the
behavior I mention a bug?
I'd say you are right, and the reason for the bug is that ETuple changed
after Polydict was written. Compare 5c1f8e65 to 79db8b7f.
Actually, I have the impression that there are several problems mixed there:
- Regardless of the value of force_etuples, PolyDict uses the class
ETuple (at line 95): to me this is a first problem since force_etuples
does not work as intended;
- The class ETuple was rewritten by Joel B. Mohler in March 2008 (commit
5813bbb4) and then improved in ticket #10834 by Mario Pernici (commit
9a60cc3a). These two commits together forbid one to use non-int
exponents in ETuple.
There are at least two possible workarounds for these problems I guess:
- Make the force_etuples and force_int_exponents have their intended
behavior by not using ETuple if force_etuples or force_int_exponents is
False. Note that both arguments have the same consequences so could be
merged. One problem is that many methods of PolyDict explicitly use
ETuple and I have not checked if and how this can be avoided.
- Make Etuple accept non-int exponents, maybe with a optional argument
to keep the fast implementation for int exponents while allowing a
slower implementation for non-int exponents. In such case, the
force_int_exponents and force_etuples arguments may be removed.
Another possibility, that I do not like but that other people may
prefer, is to keep the ETuple and PolyDict classes as they are now,
simply removing the arguments force_etuples and force_int_exponents
since they have no effect.
I feel like it is a shame that PolyDict only handle int exponents, and
to me this was a regression when ETuple was rewritten. What do you
think? At least, the current documentation does not agree with the behavior.
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