On Monday, December 1, 2014 9:46:04 AM UTC-8, Ben Hutz wrote:
>
> D={}
> for t in G:
> D.update({t:[F(t)]})
>
The keys here aren't necessarily a problem yet, provided "preperiodic" is
careful. However, the values here are computed from an imprecise t and
you're hoping that their values will be *exactly* equal to one of the
elements in G. This can't work. you're doing numerical work so you'll have
to choose an epsilon to do your comparison.
Interval fields apparently hide this (intervals are "equal" if they have
non-empty intersection?), but of course hash cannot respect this, because
this notion of "equality" isn't transitive. The bug is that CIF elements
are hashable at all.
Instead of using CIF elements as keys you should use abstract labels and
you should build your graph by looking up the abstract labels, or normalize
your labels to be exactly the elements originally put in G. Naively that's
O(n^2), but with some sort you might be able to speed that up if necessary.
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