  We perform a systematic study of the spin polarization of hyperons in
heavy-ion collisions using the MUSIC hydrodynamic model with A Multi-Phase
Transport (AMPT) pre-equilibrium dynamics. Our model calculations nicely
describe the measured collision-energy, centrality, rapidity, and $p_T$
dependence of $\Lambda$ polarization. We also study and predict the global spin
polarization of $\Xi^-$ and $\Omega^-$ as a function of collision energy, which
provides a baseline for the studies of the magnetic moment, spin, and mass
dependence of the spin polarization. For the local spin polarization, we
calculate the radial and azimuthal components of the transverse $\Lambda$
polarization and find specific modulating behavior which could reflect the
circular vortical structure. However, our model fails to describe the
azimuthal-angle dependence of the longitudinal and transverse $\Lambda$
polarization, which indicates that the hydrodynamic framework with the spin
Cooper-Frye formula under the assumption of thermal equilibrium of spin degree
of freedom needs to be improved.
