//FeedforwardNode.cpp
//
//Function definitions for the FeedForward node class.
//

#ifndef FEEDFN_C
#define FEEDFN_C

#include <math.h>
#include "FeedforwardNode.h"

FeedforwardNode::FeedforwardNode () {}

//copy constructor
FeedforwardNode::FeedforwardNode (const FeedforwardNode &fnode) {
  error = fnode.error;
}

//--------assignment operator----------
FeedforwardNode& FeedforwardNode::operator= (const FeedforwardNode &fnode) {
  if (this != &fnode) {
    Node<double>::operator= (fnode);  //we don't care about the value of the error --
                                      //it becomes meaningless as we change the network
  }
  return *this;
}

//---------activation functions----------
double FeedforwardNode::activation (double threshold = 0) {
  double net = 0;
  for (int counter = 0; counter < numberInputConnections; ++counter) {
    net += inputWeight[counter].readWeight () * (inputWeight[counter].readNodePointer())->readActivation();
  }
  output = activationFunction(net, threshold);
  return output;
}

double FeedforwardNode::firstHiddenLayerActivation (double *inputVector, double threshold = 0) {
  double net = 0;
  for (int counter = 0; counter < numberInputConnections; ++counter) {
	 net += inputWeight[counter].readWeight() * *(inputVector+counter);
  }
  output = activationFunction(net, threshold);
  return output;
}

inline double FeedforwardNode::activationFunction (double net, double threshold = 0) {
  if (net > 10) return 1;
	 else {if (net < -10) return 0;
		else return 1/(1+exp(-net+threshold));
    }
}

//---------readers--------------
inline double FeedforwardNode::readError () {return error;}

#endif