Use this command to pass experimental spectra to a CODE reflectance or transmittance spectrum.

The 'Index' parameter gives the index of the spectrum in the list of spectra (counted like 1, 2, 3, ...). The spectral positions (wavelengths, frequencies, wavenumbers, energies) and data (reflectance or transmittance) are passed through variant arrays - they must be 1-dimensional and of the same length. The parameter 'unit_string' sets the spectral unit (eV, 1/cm, THz, nanometer, wavenumber).