code: @Override
      public void setEntry(int row, int column, double value) throws OutOfRangeException {
          MatrixUtils.checkRowIndex(this, row);
          MatrixUtils.checkColumnIndex(this, column);
          if(value == 0.0) {
              entries.remove(computeKey(row, column)); //if it is exactly 0.0 don't store it. Also make sure you remove any previous key.
          }
          else {
              entries.put(computeKey(row, column), value);
          }
      }
docs: {@inheritDoc}