Sets special dependencies so that parameters depend on other parameters. (i.e., 'prmX ~ conda == -(prmY ~ condb)')
flex_special_dependency(flex_prms_obj, formula_instr)a modified flex_prms_object with a modified (linear) internal list and modified parameter and custom parameter matrices
a flex_prms object
a string referring to "special dependency" (see modify_flex_prms)