RPF: An Extensible, Cross-Platform, Binary File Format for Radiation Physics Data

Abstract

Lawrence Livermore National Laboratory's Radiation Technology Group (RTG) uses a number of computer codes for simulation and analysis of radiation data. The number of incompatible data formats that these data presented themselves in have continued to multiply. In the 1980's a Common Data Format (CDF, see Appendix A) was devised for internal use by the RTG. This format represented a single gamma-ray spectrum as ASCII energy/count pairs preceded by an ASCII header. The ASCII representation of the data assured that it was compatible on any computing platform and this format is still in use. In the mid 1990's it became apparent that instrument systems of greater complexity would demand a file format of larger capacity to support systems then on the drawing board, including networks of sensors collecting time series of gamma-ray spectra. These systems were in the planning stage and defined data structures were not available. It became apparent that a new storage format for nuclear measurements data would be needed and it would have to be flexible and extensible to accommodate the requirements of systems of the future. As part of an LDRD, we began to investigate what others were doing, especially in the high-energy physics community, tomore » deal with the large volumes of data being generated. Of particular interest was the very general Hierarchical Data Format (HDF), developed and maintained by the National Center for Supercomputing Applications (NCSA), that we ultimately used to develop the Radiation Physics Format (RPF). The HDF subroutine library provides users with the ability to customize a data file format based on standard calls to the HDF subroutine library. The RPF was developed and deployed on Sun and Hewlett-Packard workstations running their proprietary versions of UNIX.« less