WVT Binning is a spatially adaptive 2-dimensional binning algorithm, designed to bin sparse X-ray data. It can handle background subtracted, exposure corrected data to produce intensity images, hardness ratio maps, or temperature maps. We have already successfully applied WVT Binning to bin X-ray data of galaxy clusters, individual galaxies, and supernova remnants, as well as integral field spectroscopy from SAURON. Details about WVT Binning are described in "Adaptive Binning of X-ray Data with Weighted Voronoi Tesselations" (Diehl & Statler 2006). The algorithm is an extension of Cappellari & Copin's (2003) Voronoi binning code.

The algorithm uses Weighted Voronoi Tesselations (WVT) to produce a very compact binning structure with a constant S/N per bin. The bin size adjusts to the required resolution in single-pixel steps, which minimizes the scatter around the target S/N. The code is very versatile and can in principle be applied to any type of data. The user manual contains instructions on how to apply the WVT binning code to X-ray data and how to extend the algorithm to other problems.

- The original paper describing the algorithm: "Adaptive Binning of X-ray data with Weighted Voronoi Tesselations", MNRAS, 368, 497 (pdf, ps)
- WVT Binning Users' Manual (pdf, ps)
- Extended IDL help for WVT binning
- Test case for WVT_IMAGE (Perseus)
- Test case for WVT_XRAYCOLOR (Perseus)
- Example csh/CIAO/S-lang/Sherpa/ script on how to produce temperature maps (tar.gz)
- Download the source code (tar.gz)
- Download everything: manual, code, test cases (tar.gz)
- Individual files

WVT Binning is a generalization of Cappellari & Copin's Voronoi binning algorithm. If you find this algorithm useful for you analysis, we ask you to cite both papers, e.g. *"We made use of the WVT binning algorithm by Diehl & Statler (2006), which is a generalization of Cappellari & Copin's (2003) Voronoi binning algorithm."*

- Diehl, Steven & Statler, Thomas S. 2006,
*"Adaptive Binning of X-ray data with Weighted Voronoi Tesselations"*, MNRAS, 368, 497 - Cappellari, Michele & Copin, Yannick 2003,
*"Adaptive spatial binning of integral-field spectroscopic data using Voronoi tessellations"*, MNRAS, 342, 345

WVT Binning is provided free of charge, and without any warranty. For more detailed copyright information, please refer to the header of WVT_BINNING.PRO

If you have any questions about the functionality of the algorithm, please send an email to diehl@helios.phy.ohiou.edu We also appreciate any bug reports and/or suggestions for improvement of the code. Feel free to contact me if you have trouble to apply WVT binning to other types of data.

- Version 2.0: First published version (12/05/2005)