Nexus reader can't read rotation_angle data

[louise-davies]

Attempting to load the entry1/tomo_entry/data/rotation_angle variable from this file (https://github.com/DiamondLightSource/Savu/blob/master/test_data/data/24737_fd.nxs) either causes Paraview to crash with a memory allocation error:

ERROR: In /var/pvw/pv/ParaView-SC17-5.5-EGL/src/VTK/Common/Core/vtkGenericDataArray.txx, line 394
vtkDoubleArray (0x6b7d5b0): Unable to allocate 816489068736 elements of size 8 bytes.

or reports that it can't read the data:

HDF5-DIAG: Error detected in HDF5 (1.8.13) thread 0:
#000: /var/pvw/pv/ParaView-SC17-5.5-EGL/src/VTK/ThirdParty/hdf5/vtkhdf5/src/H5Dio.c line 173 in vtk__H5Dread(): can't read data
major: Dataset
minor: Read failed
#1: /var/pvw/pv/ParaView-SC17-5.5-EGL/src/VTK/ThirdParty/hdf5/vtkhdf5/src/H5Dio.c line 437 in vtk__H5D__read(): no output buffer
major: Invalid arguments to routine
minor: Bad value

This file is being used as a test file for the CCPiReconstruction Paraview plugin and it needs to read in the variable in question.