solarpy.quality.closure_flag

Contents

solarpy.quality.closure_flag#

solarpy.quality.closure_flag(ghi, dni, dhi, solar_zenith, *, check='both', outside_domain_flag=False, nan_flag=False)#

Flag measurements where the three-component closure ratio exceeds plausible limits.

The closure ratio R = GHI / (DHI + DNI · cos(SZA)) is compared against solar-zenith-dependent limits when the component sum exceeds 50 W/m².

The limits are:

  • R must be within ±8% of 1.0 for solar zenith < 75°

  • R must be within ±15% of 1.0 for 75° ≤ solar zenith < 93°

  • not tested for component sum ≤ 50 W/m² or solar zenith ≥ 93°

The comparison test is part of the BSRN QC tests [1], [2].

Parameters:
  • ghi (array-like of float) – Global horizontal irradiance [W/m²].

  • dni (array-like of float) – Direct normal irradiance [W/m²].

  • dhi (array-like of float) – Diffuse horizontal irradiance [W/m²].

  • solar_zenith (array-like of float) – Solar zenith angle [degrees].

  • check ({'high-zenith', 'low-zenith', 'both'}, optional) – Which solar zenith angle domain to check. Default is 'both'.

  • outside_domain_flag (bool, optional) – Value to assign to the flag when conditions are outside the valid test boundary. Can be either True or False. Default is False, which does not flag untested values as suspicious.

  • nan_flag (bool, optional) – If True, flag values where ghi, dhi, or dni is NaN. Default is False, which does not flag NaN values as suspicious.

Returns:

flag – Boolean array. True indicates the value failed the test, False indicates it passed or was outside the test domain.

Return type:

same type as ghi

References