sip_tpv ======= Utilities for converting between the SIP convention for representing distortion in FITS images, and the TPV convention. Licensed under a 3-clause BSD style license - see LICENSE.txt This module includes the equations for converting from the SIP distortion representation to the PV or TPV representations, following the SPIE proceedings paper at http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1363103 and http://web.ipac.caltech.edu/staff/shupe/reprints/SIP_to_PV_SPIE2012.pdf . The work described in that paper is extended to 7th order. Copyright (c) 2012-2014, California Institute of Technology If you make use of this work, please cite: "More flexibility in representing geometric distortion in astronomical images," Shupe, David L.; Laher, Russ R.; Storrie-Lombardi, Lisa; Surace, Jason; Grillmair, Carl; Levitan, David; Sesar, Branimir, 2012, in Software and Cyberinfrastructure for Astronomy II. Proceedings of the SPIE, Volume 8451, article id. 84511M. Thanks to Octavi Fors for contributing code modifications for better modularization, and for extensive testing. Funding is acknowledged from NASA to the NASA Herschel Science Center and the Spitzer Science Center. Contact: David Shupe, IPAC/Caltech.