Homework 8

Throughout the debugging process, two issues were observed and fixed to run the code successfully. In the initial run, a `TypeError` was investigated via `%debug` to spot an incompatible element type, tuple, for `sum()` in `bench_optimizer()`. There was no more runtime error in the following run, but the result still looked not good; only the first optimizer had multiple function calls, while following algorithms had no single call at all. It was found that `param_grid` generator fed into each optimizer was only initialized once, but not reset for each consecutive iteration. After moving it inside the loop, everything seemed to start working fine. The final output closely resembled the sample provided in the instruction.

[Here](http://nbviewer.ipython.org/github/tomyun/2014_Astr599_HW/blob/HW8_branch/tomyun/HW8.ipynb) is a link to the notebook that describes actual debugging steps.