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Difference in fitting results compared to fortran sedfitter
In a test fit of Kurucz model atmospheres to a large (150,000) catalog of combined UKIDSS/2MASS and GLIMPSE point sources in a chunk of the Galactic midplane, I find ~10% more badly fit sources using the python sedfitter than previously with the fortran sedfitter. Best of my knowledge* all fitting parameters are the same (extinction law is your old ex_law_gl.par file, cpd=2, minimum datapoints = 4).
*Am I correct that the format/units of old extinction law files, including lots of extraneous columns, are still appropriate for the python sedfitter?
The old extinction files should still work with the new SED fitter. There was a bug I fixed in the Python SED fitter that may have been present in the old fitter that changes the reduced chi^2 values a little. Could you try and compare the chi^2 values for the best fit before and after, and see if the agreement depends on the number of valid fluxes?
Yes, I'll see if I can do that when I get some time. Would you be more interested in comparisons using kurucz atmospheres or r06 models? (I have no plans to use the old fortran fitter with the r17 models :-) )
On Thu, Jul 26, 2018 at 6:33 AM Thomas Robitaille [email protected] wrote:
The old extinction files should still work with the new SED fitter. There was a bug I fixed in the Python SED fitter that may have been present in the old fitter that changes the reduced chi^2 values a little. Could you try and compare the chi^2 values for the best fit before and after, and see if the agreement depends on the number of valid fluxes?
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