Note the following: sage: int(5).__mod__(4) NotImplemented sage: int(5).__mod__(QQ(2)) NotImplemented
If a special method returns NotImplemented, Python will try calling the special method on the second input (with the arguments in the same order). In this case, the __mod__ methods of Integer and RealNumber handle ints as their first input (check the code in Integer.__mod__ for example). In Rational.__mod__ on the other hand, the first input is declared as type Rational to Cython, and thus a TypeError is raised when Python tries to call __mod__ with inputs (int, Rational). The solution is to fix the implementation of __mod__ in rational.pyx. David On Tue, Jul 9, 2013 at 8:37 AM, Volker Braun <vbraun.n...@gmail.com> wrote: > Look at Integer.__mod__ vs. Rational.__mod__, this'll make it clear how to > fix it. > > Apparently the design decision was to call Rational.__mod__(int, Rational) > in that case. It would be nice to have some explanation why. > > > On Tuesday, July 9, 2013 6:28:20 AM UTC-4, Travis Scrimshaw wrote: >> >> >> sage: int(5) % QQ(2) >> ------------------------------**------------------------------** >> --------------- >> TypeError Traceback (most recent call >> last) >> <ipython-input-4-8ec0f9994ded> in <module>() >> ----> 1 int(Integer(5)) % QQ(Integer(2)) >> >> TypeError: Argument 'self' has incorrect type (expected sage.rings. >> rational.Rational, got int) >> >> >> -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-devel+unsubscr...@googlegroups.com. > To post to this group, send email to sage-devel@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/groups/opt_out.
