#include "MLP.h"

double frand(){
    return(2.0*(double)rand()/RAND_MAX) -1.0;
}


//Return a new Perceptron object with the specified number of inputs(+1 for the bias)
Perceptron::Perceptron(int inputs, double bias){
    this-> bias = bias;
    weights.resize(inputs+1);
    generate(weights.begin(),weights.end(),frand);

}

//Run the perceptron. x is a vector with the input values.
double Perceptron::run(vector<double>x){
    x.push_back(bias);
    double_sum = inner_product(x.begin(),x.end(),weights.begin(),(double)0.0);
    return sigmoid(sum);

}

void Perceptron::set_weights(vector<double>w_init){
    weights = w_init;
}

double Perceptron::sigmoid(double x){
    return (1.0/(1.0 + exp(-x)));
}