Testing the emulation of 1D M_ap. The solid green curve corresponds to the relative excess of the interpolated DV with respect to the measured DV. This error on the interpolation remains below 5% (dashed black lines) and small in comparison to the relative excess interpolated for a variation of 2% (doted green curve) and 5% (dashed green curve) of S₈, and to the 25 DVs used to build the emulator (blue to red curves).