Period spacing pattern in an inertial frame computed for (k, m) = (0, 1) modes in a centrifugally deformed 2.0 M_⊙, X_c = 0.50 (X_c/X_ini = 0.70), Z = 0.014, D_mix = 1 cm² s⁻¹, f_ov = 0.015 equilibrium model at Ω/Ω_c = 0.50 (blue line). The black-dashed line shows the equivalent period spacing pattern for the same model, but without the effect of the centrifugal acceleration. The red and purple lines show the results for and , respectively. The bottom panel shows the differences with respect to the spherically symmetric period spacing pattern. The indicated global errors for the periods and period spacings are averages calculated from the uncertainties of P and Δ P for a sample of 40 γ Dor stars by Van Reeth et al. (2015), where the horizontal bar is hardly visible as it represents 10⁻⁴ d.