better error message
fix for scalar variables
removed start = None
added int division to math
allow quad_potential and thus hmc to take sparse matrix and quad potentials
added .point function for getting a parameter point in a trace
fixed issue with scikits.sparse solve_A failing on column vectors
 added __all__
fixed boolean casting problem
make sure to always use division
defaults for tracecov
added __all__s
added sigmoid to import
refactored compilation of model functions
refactoring for chances to model functions
filter variables based on type
make sure to import blocking
make sample fit the number of samples intelligently
a new dict type so that you can index with variables not just their names
don't know why that was in there anyway