Multimin.Derivval make : 
  kind ->
  int ->
  Fun.multim_fun_fdf ->
  x:Vector.vector ->
  step:float ->
  tol:float ->
  tval name : t -> stringval iterate : t -> unitval restart : t -> unitval minimum : 
  ?x:Vector.vector ->
  ?dx:Vector.vector ->
  ?g:Vector.vector ->
  t ->
  floatval test_gradient : t -> float -> bool