Resimulation results of Settl-Net for the entire synthetic spectra in the test set. The left panel presents the median relative error across the wavelength range of the resimulated spectra based on the MAP predictions of the cINN trained on the Settl models averaged over the 13 107 synthetic spectra in the test set. The grey envelope indicates the interquantile range between the 25 and 75% quantiles. In the right panel, we present the histogram of the RMSEs of the 13 107 resimulated spectra. The mean resimulation RMSE across the test set is 3.01 ± 4.35 × 10⁻⁷.