PreSAXS1.0, a program package for small-angle scattering of X-ray data pre-analysis

[Background] The rapid development of small-angle scattering of X-ray (SAXS) has massively increased the speed of experiments to be performed and produced a large amount of raw data collected during each experiment. Although some software can available for batch processing, there are some difficulties in batch processing for deluged raw data, and there is no domestic batch processing available before. [Purpose] This study aims to develop a package for single and batch processing to pre-analyze SAXS/WAXS patterns and the deluge data. [Methods] Based on MATLAB platform, a semiautomatic data processing program PreSAXS 1.0 was implemented. It composed of four main capabilities: background subtraction, beam-center determination, sample-to-detector distance (SDD) calibration and the one-dimensional integrated intensity curves obtaining from deluged two-dimensional patterns. A comprehensive standard database was developed for fast indexing, and the circle fitting method was used to simulate the scattering/diffraction rings to find beam-center and calibrated SDD. The interpolation method from MATLAB was embedded in the package to improve the calculation speed. [Results] The beamcentre find, SDD calibration, and I-q curves are perfectly appropriate to Irena, Raw software. After pre-data analysis, the data are saved as ASCII code and can be used for director read or further analysis by other software. [Conclusions] PreSAXS 1.0 is easy to operate with user friendly interface, satisfies majority requirements of batch processing for SAXS data pre-analysis. However, PreSAXS 1.0 still needs to be improved, such as function extension, faster calculation speed and data analysis for GISAXS, etc. (authors)