Source code for MDAnalysis.coordinates.null

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Null output --- :mod:`MDAnalysis.coordinates.null`

The :class:`NullWriter` provides a Writer instance that behaves like
any other writer but effectively ignores its input and does not write
any output files. This is similar to writing to ``/dev/null``.

This class exists to allow developers writing generic code and tests.


.. autoclass:: NullWriter

from . import base

[docs]class NullWriter(base.WriterBase): """A trajectory Writer that does not do anything. The NullWriter is the equivalent to ``/dev/null``: it behaves like a Writer but ignores all input. It can be used in order to suppress output. """ format = 'NULL' multiframe = True units = {'time': 'ps', 'length': 'Angstrom'} def __init__(self, filename, **kwargs): pass def _write_next_frame(self, obj): try: atoms = obj.atoms except AttributeError: errmsg = "Input obj is neither an AtomGroup or Universe" raise TypeError(errmsg) from None