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tsutterley / pyTMD

Python-based tidal prediction software
https://pytmd.readthedocs.io
MIT License
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calc_astrol_longitudes.py: inconsistency between ASTRO5 and MEEUS solar perigee definition. #117

Closed eapuntel closed 2 years ago

eapuntel commented 2 years ago

Hi there @tsutterley... I noticed a divergence between two definitions on calc_astrol_longitudes.py: equations are identical, but ASTRO5 has T defined in days and MEEUS uses T in centuries.

if MEEUS: # convert from MJD to days relative to 2000-01-01T12:00:00 T = MJD - 51544.5 #... # mean longitude of solar perigee (Simon et al., 1994) PP = 282.94 + 1.7192 * T

elif ASTRO5: # convert from MJD to centuries relative to 2000-01-01T12:00:00 T = (MJD - 51544.5)/36525.0 # ... # mean longitude of solar perigee (Simon et al., 1994) PP = 282.94 + 1.7192 * T

tsutterley commented 2 years ago

Hi @eapuntel. You're absolutely right the rate was in the incorrect units. I have this fix (and a documentation build fix) in #118