Can you help explain this change to me. What I see here is that you're doing `(odf - a) / b` which is the same as `(odf / b - a /b)`, this should not at all change the result of `local_maxima` afaict unless there is a bug in `local_maxima`. It's possible that my logic is off here, but I've run the more thorough peak tests with this change reverted and all the tests pass. Before we make this change I'd like to see a testcase that demonstrates the difference.