svd.h

#ifndef SVD_H
#define SVD_H

#include <bits/stdc++.h>

using namespace std;
class Matrix;

class Svd{
private:
  Matrix* q;
  Matrix* p;
  int factors;
  int epochs;
  double learning_rate, average_rating; //average_rating used

  vector <pair<pair <int,int>, double>> dense_users;//stores ratings.csv
  vector <pair<string,string>> targets;//stores targets.csv
  // 2 dicts below keep track of user index in matrix p and item index in matrix q
  unordered_map<string,int> user_index;
  unordered_map<string,int> item_index;
public:

  Svd (int k, double learning_rate, int epochs, ifstream* input_ratings, ifstream* input_targets);
  ~Svd ();
  void read_targets(ifstream* input_targets );
  void read_ratings(ifstream* input_ratings);
  void train_model();
  double predict(int user, int item);//for a pair user:item, predicts a rating
  void submission();

};

#endif