code: private void addRelation(String object, String attribute) {
          double val;
          int row, col;
  
          object = object.toLowerCase();
          attribute = attribute.toLowerCase();
  
          // get row in matrix
          if( objectTable.containsKey(object) ) {
              // if the object already exists in matrix, find its index
              row = objectTable.get(object);
          } else {
              // otherwise give the object a new index number
              row = Integer.valueOf(objectCounter.getAndIncrement());
              // insert new object/index pair into lookup table
              objectTable.put( object, row );
              System.out.println(object + " " + row);
          }
  
          // get column in matrix
          if( attributeTable.containsKey(attribute) ) {
              col = attributeTable.get(attribute);
          } else {
              col = Integer.valueOf(attributeCounter.getAndIncrement());
              attributeTable.put( attribute, col );
          }
  
          // update entry in matrix which records how many times the
          // object/attribute pair has been seen
          if( row < syntacticCooccurrence.rows() && 
              col < syntacticCooccurrence.columns()) {
              // if there's already an entry for the object and attribute, get the
              // current value for the pair of words
              val = syntacticCooccurrence.get(row, col);
              // increment the current value by one and store in matrix
              syntacticCooccurrence.set(row, col, val+1);
          } else {
              // otherwise set the row, col value to 1
              syntacticCooccurrence.set(row, col, 1.0);
          }
      }
docs: Adds a relation pair to the matrix