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# numpy.fromfile

numpy.fromfile(file, dtype=np.float64, count=-1, sep='', offset=0, *, like=None)

  Construct an array from data in a text or binary file.

  A highly efficient way of reading binary data with a known data-type, as well as parsing simply formatted text files. Data written using the tofile method can be read using this function.

  Parameters:
    file file or str or Path

      An open file object, a string containing the filename, or a Path object. When reading from a file object it must support random access (i.e. it must have tell and seek methods).

    dtype data-type

      Data type of the returned array. For binary files, it is used to determine the size and byte-order of the items in the file. Most builtin numeric types are supported and extension types may be supported.

    count int

      Number of items to read. `-1` means all items (i.e., the complete file).

    sep str

      Separator between items if file is a text file. Empty (“”) separator means the file should be treated as binary. Spaces (” “) in the separator match zero or more whitespace characters. A separator consisting only of spaces must match at least one whitespace.

    offset int

      The offset (in bytes) from the file’s current position. Defaults to 0. Only permitted for binary files.

    like array_like, optional

      Reference object to allow the creation of arrays which are not NumPy arrays. If an array-like passed in as `like` supports the `__array_function__` protocol, the result will be defined by it. In this case, it ensures the creation of an array object compatible with that passed in via this argument.

      New in version 1.20.0.

  See also

  `load`, `save`
  `ndarray.tofile`
  `loadtxt`

    More flexible way of loading data from a text file.

  Notes

  Do not rely on the combination of tofile and `fromfile` for data storage, as the binary files generated are not platform independent. In particular, no byte-order or data-type information is saved. Data can be stored in the platform independent `.npy` format using `save` and `load` instead.

  Examples

  Construct an ndarray:

      >>> import numpy as np
      >>> dt = np.dtype([('time', [('min', np.int64), ('sec', np.int64)]),
      ...                ('temp', float)])
      >>> x = np.zeros((1,), dtype=dt)
      >>> x['time']['min'] = 10; x['temp'] = 98.25
      >>> x
      array([((10, 0), 98.25)],
            dtype=[('time', [('min', '<i8'), ('sec', '<i8')]), ('temp', '<f8')])

  Save the raw data to disk:

      >>> import tempfile
      >>> fname = tempfile.mkstemp()[1]
      >>> x.tofile(fname)

  Read the raw data from disk:

      >>> np.fromfile(fname, dtype=dt)
      array([((10, 0), 98.25)],
            dtype=[('time', [('min', '<i8'), ('sec', '<i8')]), ('temp', '<f8')])

  The recommended way to store and load data:

      >>> np.save(fname, x)
      >>> np.load(fname + '.npy')
      array([((10, 0), 98.25)],
            dtype=[('time', [('min', '<i8'), ('sec', '<i8')]), ('temp', '<f8')])