Decomposing and combining irradiance

irradiance.get_extra_radiation(datetime_or_doy)	Determine extraterrestrial radiation from day of year.
irradiance.aoi(surface_tilt, ...)	Calculates the angle of incidence of the solar vector on a surface.
irradiance.aoi_projection(surface_tilt, ...)	Calculates the dot product of the sun position unit vector and the surface normal unit vector; in other words, the cosine of the angle of incidence.
irradiance.beam_component(surface_tilt, ...)	Calculates the beam component of the plane of array irradiance.
irradiance.poa_components(aoi, dni, ...)	Determine in-plane irradiance components.
irradiance.get_ground_diffuse(surface_tilt, ghi)	Estimate diffuse irradiance on a tilted surface from ground reflections.
irradiance.dni(ghi, dhi, zenith[, ...])	Determine DNI from GHI and DHI.
irradiance.complete_irradiance(solar_zenith)	Use the component sum equations to calculate the missing series, using the other available time series.
irradiance.diffuse_par_spitters(...)	Derive daily diffuse fraction of Photosynthetically Active Radiation (PAR) from daily average solar zenith and diffuse fraction of daily insolation.