#include<iostream>
#include<cmath>
using namespace std;
#include"individual.h"

const int NUM_POINTS = 5; // test points
// inputs are x values, outputs are f(x) values
float inputs[NUM_POINTS] = {1,2,3,4,5};
float outputs[NUM_POINTS] = {1,4,9,16,25};

/* calls a recursive function to erase/free the tree.
*/
void indiv::erase(void){
	the_indiv -> erase();
}

/* Generates a random full tree.
*/
void indiv::generate(int max_depth){
	the_indiv = new node;
	the_indiv->full(0,max_depth,NULL);
}


/* Calculates the size of an individual's tree.*/
void indiv::calc_size(void){
	terms = 0;
	non_terms = 0;
	size = 0;			
	the_indiv-> calc_size(terms,non_terms);
	size += (terms + non_terms);
}

void indiv::mutate(){
     the_indiv->mutate();
}

/* Calculates fitness.
For the symbolic regression problem it has to reevaluate the expression 
tree for each of the X points.  
The square root of the sum of the squared errors at each of those
points is the fitness.
*/
void indiv::evaluate(void){  
	fitness = 0;
	float output;
	for(int j=0; j < NUM_POINTS; j++){
		// evaluate function on each input point
		output = the_indiv-> evaluate(inputs[j]);
		fitness += (pow((output-outputs[j]),2));
		// outputs array holds correct values 
	}
	fitness = sqrt(fitness);
}

/* Evalautes the tree and prints the y value for each of the x values.*/
void indiv::evaluate_print(void){
/* evaluates a tree and prints the outputs and 
correct outputs */
	fitness = 0;
	float output;
	for(int j=0; j < NUM_POINTS; j++){
		output = the_indiv-> evaluate(inputs[j]);
		fitness += (pow((outputs[j]-output),2));
		// outputs array holds correct values 
		cout << inputs[j] << "," << output << "," << outputs[j] << " , " ;
	}
	fitness = sqrt(fitness); // square root of the sum of the squared errors
	cout << endl << "Fitness = " << fitness << endl;
}