def to_complex_field(self):
"""
Return the ComplexField stored on disk.
.. note::
The mesh stored on disk must be stored with ``mode=complex``
Returns
-------
real : pmesh.pm.ComplexField
an array-like object holding the mesh loaded from disk in Fourier
space
"""
if not self.isfourier:
return NotImplemented
pmread = self.pm
if self.comm.rank == 0:
self.logger.info("reading complex field from %s" % self.path)
with FileMPI(comm=self.comm, filename=self.path)[self.dataset] as ds:
complex2 = ComplexField(pmread)
assert self.comm.allreduce(complex2.size) == ds.size
start = numpy.sum(self.comm.allgather(complex2.size)[:self.comm.rank], dtype='intp')
end = start + complex2.size
complex2.unravel(ds[start:end])
return complex2
