This code searches for the best combination of two reference spectra able to reproduce the observed spectrum of the system. We give, as input parameters, the radial velocities and projected rotational velocities of the two components of the system, which were already derived. The code then finds, for the selected spectral region, the spectral types and fractional flux contributions that best reproduce the observed spectrum, i.e. which minimize the residuals in the collection of difference (observed$-$composite) spectra. For this task we used reference spectra taken from the @Val04 $Indo-U.S.\ Library\ of\ 
Coude\ Feed\ Stellar\ Spectra$ (with a a resolution of $\approx$1Å) that are representative of stars with spectral types from late-O type to early-M, and luminosity classes V, IV, and III. The atmospheric parameters of these reference stars were recently revised by @Wu2011.

We selected 198 reference spectra spanning the ranges of expected atmospheric parameters, which means that we have searched for the best combination of spectra among 39204 possibilities per spectrum. The observed spectra of V2653Oph in the $\lambda$4960–5000 spectral region were best represented by the combination of HD183085 (F0.5V) and $\iota$ Psc (F7V). However, we have adopted, for each component, the spectral type and luminosity class with the 