Different Δk binning for the FAST surveys. The plot shows the fractional error in the power spectrum versus wave number k at a redshift of z = 0.9 for the FAST surveys. All the other survey parameters are the same as for Fig. 1. Here we use a binning scheme for FAST where Δk = k (see Eq. (7)). The different FAST survey configurations are green for survey 1, red for survey 2, and blue for survey 2 with two years of observations.