FIM_emax_3par(x, w, param)x and sum(w) should be 1.FIM_comp_inhibition,
FIM_exp_2par, FIM_exp_3par,
FIM_logisitic_1par,
FIM_logistic_4par,
FIM_logistic, FIM_loglin,
FIM_michaelis,
FIM_mixed_inhibition,
FIM_noncomp_inhibition,
FIM_power_logistic,
FIM_uncomp_inhibition