code: public SDVariable eye(String name, int rows, int cols, DataType dataType) {
          return eye(name, rows, cols, dataType);
      }
docs: Generate an identity matrix with the specified number of rows and columns
  Example:<br>
  <pre>
  {@code SDVariable eye = eye(3,2)
  eye:
  [ 1, 0]
  [ 0, 1]
  [ 0, 0]}
  </pre>
  
  @param name Name of the new SDVariable
  @param rows Number of rows
  @param cols Number of columns
  @return SDVaribable identity matrix