Module « scipy.io »

Classe « FortranFile »

Informations générales

Héritage

builtins.object
    FortranFile

Définition

class FortranFile(builtins.object):

Description _{[extrait de FortranFile.__doc__]}

    A file object for unformatted sequential files from Fortran code.

    Parameters
    ----------
    filename : file or str
        Open file object or filename.
    mode : {'r', 'w'}, optional
        Read-write mode, default is 'r'.
    header_dtype : dtype, optional
        Data type of the header. Size and endiness must match the input/output file.

    Notes
    -----
    These files are broken up into records of unspecified types. The size of
    each record is given at the start (although the size of this header is not
    standard) and the data is written onto disk without any formatting. Fortran
    compilers supporting the BACKSPACE statement will write a second copy of
    the size to facilitate backwards seeking.

    This class only supports files written with both sizes for the record.
    It also does not support the subrecords used in Intel and gfortran compilers
    for records which are greater than 2GB with a 4-byte header.

    An example of an unformatted sequential file in Fortran would be written as::

        OPEN(1, FILE=myfilename, FORM='unformatted')

        WRITE(1) myvariable

    Since this is a non-standard file format, whose contents depend on the
    compiler and the endianness of the machine, caution is advised. Files from
    gfortran 4.8.0 and gfortran 4.1.2 on x86_64 are known to work.

    Consider using Fortran direct-access files or files from the newer Stream
    I/O, which can be easily read by `numpy.fromfile`.

    Examples
    --------
    To create an unformatted sequential Fortran file:

    >>> from scipy.io import FortranFile
    >>> f = FortranFile('test.unf', 'w')
    >>> f.write_record(np.array([1,2,3,4,5], dtype=np.int32))
    >>> f.write_record(np.linspace(0,1,20).reshape((5,4)).T)
    >>> f.close()

    To read this file:

    >>> f = FortranFile('test.unf', 'r')
    >>> print(f.read_ints(np.int32))
    [1 2 3 4 5]
    >>> print(f.read_reals(float).reshape((5,4), order="F"))
    [[0.         0.05263158 0.10526316 0.15789474]
     [0.21052632 0.26315789 0.31578947 0.36842105]
     [0.42105263 0.47368421 0.52631579 0.57894737]
     [0.63157895 0.68421053 0.73684211 0.78947368]
     [0.84210526 0.89473684 0.94736842 1.        ]]
    >>> f.close()

    Or, in Fortran::

        integer :: a(5), i
        double precision :: b(5,4)
        open(1, file='test.unf', form='unformatted')
        read(1) a
        read(1) b
        close(1)
        write(*,*) a
        do i = 1, 5
            write(*,*) b(i,:)
        end do

    

Constructeur(s)

Signature du constructeur	Description
__init__(self, filename, mode='r', header_dtype=<class 'numpy.uint32'>)

Liste des opérateurs

Opérateurs hérités de la classe object

__eq__, __ge__, __gt__, __le__, __lt__, __ne__

Méthodes héritées de la classe object

__delattr__, __dir__, __format__, __getattribute__, __hash__, __init_subclass__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __str__, __subclasshook__