  For L1(0) FePt films, the anomalous Hall resistivity is found to be
proportional to spontaneous magnetization $M_{\mathrm{S}}$. After the
$M_{\mathrm{S}}$ temperature effect is eliminated, $\rho_{\mathrm{xyo}}$ can be
fitted by $\rho_{\mathrm{xyo}}=a_{\mathrm{o}}\rho_{\mathrm{xx}}+
b_{\mathrm{o}}\rho_{\mathrm{xx}}^{\mathrm{2}}$. $a_{\mathrm{o}}$ and
$b_{\mathrm{o}}$ change non-monotonically with chemical long range ordering
degree $S$. Accordingly, it is indicated that for L1(0) FePt films the spin
orbit coupling strength increases monotonically with increasing $S$.
