From ptak at cmu.edu Tue Apr 4 15:17:06 2000 From: ptak at cmu.edu (ptak at cmu.edu) Date: Tue, 4 Apr 2000 15:17:06 -0400 (EDT) Subject: [AstroPy] ximgfit Python application Message-ID: Hello, I have a python astronomy program that is fairly usable right now. Its "version" is 0.96 because there are still some features I would like to add, and most of the debugging has occured through my use of the program rather than a real attempt to break it (and hence the most robust features are the ones I use often). Its main purpose is to fit FITS images with spatial models with emphasis on X-ray images where the pixels represent low numbers of counts, i.e., in the Poisson statistical regime, optionally also convolving the model with a PSF image (using the fftw library). Its default fit statistic is chi^2 so it is usuable for optical, etc. work also. The bells and wistles that help out with X-ray data are: - Use of the Cash's C (Poissonian) fit statistic - Automated stepping of the fit parameters to get errors, including starting over when a new minimum is found - Genetic algorithm fitting (implimented entirely in Python) as a global-minimization fit technique - XSPEC-style syntax (XSPEC is the defacto standard X-ray spectral fitting package). Since it combines Numeric, fftw, and my C++ fits routines, I haven't gotten around to a source release but Linux and Solaris binaries (as well as an online manual) are available at http://snooker.phys.cmu.edu/ximgfit/ I am using it daily (both interactively and in bgd. jobs) on Chandra and ROSAT data. If nothing else, it is an example of an actual astronomy application written (mostly) in Python. This program is the spatial component of a larger project to automate the analysis of X-ray data (particularly the error search feature). Cheers, Andy Ptak ptak at cmu.edu _____________________________________________________ AstroPy mailing list - astropy at stsci.edu http://lheawww.gsfc.nasa.gov/~bridgman/AstroPy/ From deoradh at yahoo.com Sun Apr 16 23:37:55 2000 From: deoradh at yahoo.com (Keith J. Farmer) Date: Sun, 16 Apr 2000 20:37:55 -0700 Subject: [AstroPy] VSOP implementation Message-ID: How much interest is there in a routine to compute coordinates based on the VSOP tables? I've already implemented the polynomial expressions (Astron Algorithms 2nd ed) on the HP49, and it's a rather speedy computation (Jupiter-Neptune in <0.5sec on a 4MHz Saturn processor). Keith Farmer San Francisco, CA __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com _____________________________________________________ AstroPy mailing list - astropy at stsci.edu http://lheawww.gsfc.nasa.gov/~bridgman/AstroPy/ From deoradh at yahoo.com Mon Apr 17 00:08:30 2000 From: deoradh at yahoo.com (Keith J. Farmer) Date: Sun, 16 Apr 2000 21:08:30 -0700 Subject: [AstroPy] VSOP implementation In-Reply-To: Message-ID: I wrote: > How much interest is there in a routine to compute coordinates > based on the > VSOP tables? I've already implemented the polynomial expressions (Astron Just saw the sources are mentioned in the PyEphem package. In that case, anyone interested in a routine to create the 5th-degree polys? I've got an idea to do it much more quickly than sampling points, which I've not really seen mentioned. Come to think of it, VSOP doesn't seem to get mentioned very often, itself. __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com _____________________________________________________ AstroPy mailing list - astropy at stsci.edu http://lheawww.gsfc.nasa.gov/~bridgman/AstroPy/ From wtbridgman at Radix.Net Sun Apr 30 17:24:16 2000 From: wtbridgman at Radix.Net (W.T. Bridgman) Date: Sun, 30 Apr 2000 17:24:16 -0400 Subject: [AstroPy] May 2000 - AstroPy Monthly Notice Message-ID: This is a monthly notice sent by the managers of the AstroPy Mailing List reminding you that your list subscription is still operational. The AstroPy web page is located at http://lheawww.gsfc.nasa.gov/~bridgman/AstroPy/ Links to Tom Loredo's and Andy Ptak's Python software have been added. If you are interested in having any astronomical Python-related announcements, etc. included in this monthly reminder, please contact the list administrators: Tom Bridgman (bridgman at wyeth.gsfc.nasa.gov) or Paul Barrett (barrett at stsci.edu). _____________________________________________________ AstroPy mailing list - astropy at stsci.edu http://lheawww.gsfc.nasa.gov/~bridgman/AstroPy/