Simon King wrote: > I think quite often one is in a situation that one has two different > sets (rings, groups, ...) S1, S2, such that there is only one action of > S1 on S2 from the left, and thus if one has s1 from S1 and s2 from S2, > then s1*s2 is not ambiguous.
I guess it depends what exactly you mean by "only one action of S1 on S2": think of S1 = K[x][d/dx] and S2 = K[x]. Differential operators act on polynomials (e.g., d/dx(x) = 1), but there is also an embedding of K[x] into K[x][d/dx] under which d/dx*x = x*d/dx+1. The internal multiplication of K[x][d/dx] applied in this context is not a left action of K[x][d/dx] _on K[x]_, but I would definitely expect (d/dx)*x to coerce x to K[x][d/dx] and multiply there. -- Marc -- 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.
