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scipy.io.

# hb_read

scipy.io.hb_read(path_or_open_file, *, spmatrix=True)

  Read HB-format file.

  Parameters:
    path_or_open_filepath-like or file-like

      If a file-like object, it is used as-is. Otherwise, it is opened before reading.

    spmatrixbool, optional (default: True)

      If `True`, return sparse `coo_matrix`. Otherwise return `coo_array`.

  Returns:
    datacsc_array or csc_matrix

      The data read from the HB file as a sparse array.

  Notes

  At the moment not the full Harwell-Boeing format is supported. Supported features are:

  > - assembled, non-symmetric, real matrices

  > - integer for pointer/indices

  > - exponential format for float values, and int format

  Examples

  We can read and write a harwell-boeing format file:

      >>> from scipy.io import hb_read, hb_write
      >>> from scipy.sparse import csr_array, eye
      >>> data = csr_array(eye(3))  # create a sparse array
      >>> hb_write("data.hb", data)  # write a hb file
      >>> print(hb_read("data.hb", spmatrix=False))  # read a hb file
      <Compressed Sparse Column sparse array of dtype 'float64'
          with 3 stored elements and shape (3, 3)>
          Coords  Values
          (0, 0)  1.0
          (1, 1)  1.0
          (2, 2)  1.0