function lmfit_adapt,fn_name,x,ymeas,ymeas_error,initial_guess,use_lmfit=use_lmfit,_extra=extra,functargs=functargs,perror=perror,covar=covar
  if keyword_set(use_lmfit) then begin
    common lm_fit_adapt,function_name,args
    function_name=fn_name
    if n_elements(functargs) gt 0 then args=functargs
    a=initial_guess
    result=lmfit(function_name="lmfitfun_adapt_function",   $ ;Function to call
               x,ymeas,a,measure_errors=ymeas_error,$
               sigma=perror)                                   ;Collect the parameter errors
    coefs=a
  end else begin
    coefs=mpfitfun(fn_name,                  $ ;Function to call
               x,ymeas,ymeas_error,          $ ;Independent var, dependent var, errors on each dependent var
               initial_guess,                $ ;Initial model coefficient guess
               perror=perror,covar=covar,    $ ;Collect the parameter errors
               functargs=functargs,          $ ;Extra stuff to pass along to the model function
               _extra=extra)
  end
  return,coefs
end