LABA 2

//
//  main.cpp
//  lab2
//
//  Created by kosha on 17/02/2020.
//  Copyright © 2020 kosha. All rights reserved.
//

#include <iostream>
#include "mlisp.h"
double xmin= 0.;
double xa, xb, ya, yb;
double tolerance= 0.00001;
double mphi = (3. - sqrt(5.)) /2.;
double a = 3.;
double b = 4.;
double fun( double x ){
    x = x - 100./101.;
    return (x + sin(2*x - 0.25*pi) + log(x+1) - 0.5);
}
double close__enough_Q(double x,double y);
double close__enough_Q(double x,double y){
    return ( abs(x - y) < tolerance);
}

double _CNA_try(double a, double b, double xa, double ya, double xb, double yb);
double _CNA_try(double a, double b, double xa, double ya, double xb, double yb){
    close__enough_Q(a,b) ? ((a+b) * 0.5) : (
        display("+"),
        (ya < yb) ? (b =xb, xb = xa, yb = ya, xa = a + (mphi * (b-a)), _CNA_try(a,b,xa,fun(xa),xb,yb)) : ( a= xa, xa =xb, yb = ya, xb = (b = mphi*(b-a)), _CNA_try(a,b, xa, ya, xb, fun(xb))
    ));

}
double golden_start(double a, double b);
double golden_start(double a, double b){
    xa = a + mphi * (b-a);
    xb = b - mphi * (b-a);
    return _CNA_try (a, b, xa, fun(xa), xb, fun(xb));

}

double golden_section_search(double a, double b);

double golden_section_search(double a, double b){
    {
        (a < b) ? xmin = golden_start(a,b) : xmin = golden_start (b,a);
    }
    newline();
    return xmin;
}



int main(){
    xmin = golden_section_search(a,b);
    display("interval=\t");
    display(a);
    display(" , ");
    display(b);
    display("]\n");
    display("xmin=\t\t");
    display(xmin);
    display("f(xmin)=\t");
    fun(xmin);
}