The top panels from left to right depict the three nonzero Stokes vector elements I_da/I₀, Q_da/I₀, U_da/I₀, and the resulting degree of linear polarization, p_da, of stellar radiation reflected by the exoplanet as it rotates around its host star. These simulations have been carried out using Mie computations (solid lines) and their HGR/TTHG approximations (dotted/dashed lines) for three different characteristic radii of the size distribution of the cloud grains: r₀ = 0.1 μm (blue), r₀ = 1 μm (green), and r₀ = 10 μm (red). The bottom panels show the corresponding errors incurred due to the approximation, with ΔI_da/I₀ on the left representing the percentage error in the HGR/TTHG approximation of I_da/I₀ with respect to its Mie computation. The following three panels show the errors ΔQ_da/I₀, ΔU_da/I₀, and Δp_da as simple differences of the HGR approximation with respect to the Mie value.