code: public void readCoordinate(int[] row, int[] column, double[] data)
              throws IOException {
          int size = row.length;
          if (size != column.length || size != data.length)
              throw new IllegalArgumentException(
                      "All arrays must be of the same size");
          for (int i = 0; i < size; ++i) {
              row[i] = getInt();
              column[i] = getInt();
              data[i] = getDouble();
          }
      }
docs: Reads a coordinate matrix