comments in test

pep8

bug fix, int32 to int64, for failure in test_multinomial.py:test_n_samples_compatibility

fixed some bugs

casting problem in c code fixed

fixed more bugs and added into both old and new backend

fixed more bugs and added into both old and new backend

bug fix

pep8

minor fix

pep8fix

pep8 fix

too much memroy?, try something smaller

refactored tests

refactored tests and pep8 fail on --select=E121