F#简易符号求导程序

来源：互联网发布：淘宝买家手机号采集器编辑：程序博客网时间：2024/05/16 09:18

> type Fexpr =  | Const of float  | X  | Add of Fexpr * Fexpr  | Sub of Fexpr * Fexpr  | Mul of Fexpr * Fexpr  | Div of Fexpr * Fexpr  | Sin of Fexpr  | Cos of Fexpr  | Log of Fexpr  | Exp of Fexprval D : _arg1:Fexpr -> Fexpr> let rec D = function  | Const _  -> Const 0.0  | X -> Const 1.0  | Add(fe, ge) -> Add(D fe, D ge)  | Sub(fe, ge) -> Sub(D fe, D ge)  | Mul(fe, ge) -> Add(Mul(D fe,ge), Mul(fe, D ge))  | Div(fe, ge) -> Div(Sub(Mul(D fe, ge), Mul(fe, D ge)), Mul(ge, ge))  | Sin fe -> Mul(Cos fe, D fe)  | Cos fe -> Mul(Const -1.0, Mul(Sin fe, D fe))  | Log fe -> Div(D fe, fe)  | Exp fe -> Mul(Exp fe, D fe);;val D : _arg1:Fexpr -> Fexpr> D(Sin (Mul(X, X)));;val it : Fexpr =  Mul (Cos (Mul (X,X)),Add (Mul (Const 1.0,X),Mul (X,Const 1.0)))> D(Mul(Const 3.0, Exp X));;val it : Fexpr =  Add (Mul (Const 0.0,Exp X),Mul (Const 3.0,Mul (Exp X,Const 1.0)))>

0 0