DNI estimation models

irradiance.disc(ghi, solar_zenith, ...[, ...])	Estimate Direct Normal Irradiance from Global Horizontal Irradiance using the DISC model.
irradiance.dirint(ghi, solar_zenith, times)	Determine DNI from GHI using the DIRINT modification of the DISC model.
irradiance.dirindex(ghi, ghi_clear, ...[, ...])	Determine DNI from GHI using the DIRINDEX model.
irradiance.erbs(ghi, zenith, datetime_or_doy)	Estimate DNI and DHI from GHI using the Erbs model.
irradiance.erbs_driesse(ghi, zenith[, ...])	Estimate DNI and DHI from GHI using the continuous Erbs-Driesse model.
irradiance.orgill_hollands(ghi, zenith, ...)	Estimate DNI and DHI from GHI using the Orgill and Hollands model.
irradiance.boland(ghi, solar_zenith, ...[, ...])	Estimate DNI and DHI from GHI using the Boland clearness index model.
irradiance.campbell_norman(zenith, transmittance)	Determine DNI, DHI, GHI from extraterrestrial flux, transmittance, and atmospheric pressure.
irradiance.louche(ghi, solar_zenith, ...[, ...])	Determine DNI and DHI from GHI using the Louche model.