sig
external central :
f:(float -> float) -> x:float -> h:float -> Gsl_fun.result
= "ml_gsl_deriv_central"
external forward :
f:(float -> float) -> x:float -> h:float -> Gsl_fun.result
= "ml_gsl_deriv_forward"
external backward :
f:(float -> float) -> x:float -> h:float -> Gsl_fun.result
= "ml_gsl_deriv_backward"
end