Foreseen constraints (1σ contours) in CPL cosmological extension wCDM for a DESI-like survey (top) and an Euclid-like survey (bottom), assuming 20 tomographic Gaussian bins of σ_z = 0.01. The blue lines are the constraints for angular galaxy clustering alone (D_g), the orange lines are for the ARF alone (D_z), and the green line is a joint analysis of both fields (D_g,  z). These contours are marginalised over the galaxy bias in the 20 redshift bins. The numbers above the parameter PDFs give the marginalised 1σ uncertainty of each parameter for each data vector.