bugfix: try to fix issue where get_spectrum gives bad model parameters
bugfix: try to fix issue where get_spectrum gives bad model parameters

mikelum/pyspeckit,vlas-sokolov/pyspeckit,allisony/pyspeckit,mikelum/pyspeckit,allisony/pyspeckit,jpinedaf/pyspeckit,e-koch/pyspeckit,vlas-sokolov/pyspeckit,pyspeckit/pyspeckit,jpinedaf/pyspeckit,keflavich/pyspeckit,e-koch/pyspeckit,low-sky/pyspeckit,low-sky/pyspeckit,pyspeckit/pyspeckit,keflavich/pyspeckit