Fit a modified black body (grey body) function to far-infrared astronomical data
Simplified version of the C code used in https://ui.adsabs.harvard.edu/abs/2019A%26A...627A..93C/abstract, intended as a teaching tool of non-linear fitting. This fits a modified black body (grey body) function to far-infrared data yielding the temperature of interstellar dust heated by ultra-violet radiation from youn stars and/or accretion onto a super-massive black hole.