Covariance matrix of the angular correlation function. Top: comparison of the correlation matrix obtained from COSMOLIKE halo model (upper diagonal) and from ICE-COLA mocks (lower diagonal). Bottom: columm of the covariance matrix Cov[] with fixed deg. The i and j subscripts correspond to the index of tha data vector (from 0 to 124, with θ ranging in [0, 5]deg in Δθ = 0.2 deg steps and four redshift bins), and N, M superscripts represent the index of the tomographic redshift bins.