Tests for #53

[bvacaliuc]

As requested, added tests for PR for #53

[coveralls]

Coverage increased (+0.4%) to 79.609% when pulling c756cfe on bvacaliuc:tests_53 into ca13028 on sethoscope:master.

[sethoscope]

Hi, Bogdan. Thanks for adding the weight handling. Bonus points for writing a test case!
I notice the test data contains 2590 points. It seems like you could test this well with just three points (one negative, one small, one large), and it would be much easier to understand. As it is, I can't tell whether the test would fail if weights were ignored.

Any interest in trying that? If not, I can aim to get to it eventually.