Use the sapm() function, the input parameters,
and self.module_parameters to calculate
Voc, Isc, Ix, Ixx, Vmp, and Imp.
- Parameters:
- 
- effective_irradiance (numeric or tuple of numeric) – The irradiance (W/m2) that is converted to photocurrent. 
- temp_cell (float or Series or tuple of float or Series) – The average cell temperature of cells within a module in C. 
 
- Returns:
- See pvsystem.sapm for details