Therefore an international team of scientists set out to develop a data exchange format during several meetings. This new format is named NeXus.
NeXus has four levels: a physical file format, a structure for ordering data in the file, a glossary of common data item names and a set of application programmers interface functions (API) for interacting with NeXus.
As physical file format the hierarchical data format (HDF) developed by the National Center for Supercomputing Applications (NSCSA), USA was choosen. HDF is an efficient binary format which is portable across machine and operating system boundaries. HDF is also self describing and extendable.
The scheme for structuring information in a NeXus file and the glossary of common data item names will facilitate the writing of general data analysis programs.
The NeXus API protects the programmer from some of the idosyncrarcies of the HDF interface and facilitates reading and writing of NeXus files.
NeXus is now coming in operation as data format for the instruments at the new spallation source SINQ at PSI. Already the first NeXus aware data evaluation prograsm exist.
(posted 19-Nov-97 jw)