Thanks to everyone who replied with suggestions, both on and off the list.
When I asked my question, I assumed there was a trivial solution that could be simply explained. I realize now that the calculations are not straightforward. Roger Bailey has given me an approach that I believe will work for me. I’m now trying to understand how the math represents the spatial geometry of the problem. The variety of solutions I received are an indication of the broad experience and wisdom embodied in this group. I'm always grateful for that asset. > On Jan 31, 2015, at 10:05 AM, John Goodman <johngood...@mac.com> wrote: > > Dear dialists, > > Does anyone know a formula for calculating the hour angle given the azimuth, > declination, and latitude? > > I’d like to know the time of day, throughout the year, when the sun will be > positioned at a particular angle. This will allow me to determine when > sunshine will stream squarely through a window on any (sunny) day. > > I’ve seen several formulae for calculating azimuth. I suspect that one of > them could be rewritten to solve for the hour angle given the azimuth instead > of the finding the azimuth using the hour angle (plus the declination and > latitude). Unfortunately, I don’t have the math skills for this conversion. > > Thanks for any suggestions. --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial