# Planetary (Density-Energy, Multi-Material) SPH¶

This scheme is the same as the Minimal SPH scheme but also allows multiple materials, meaning that different SPH particles can be assigned different Equations of State (EoS).

To use the planetary scheme and the corresponding planetary EoS, use

./configure --with-hydro=planetary --with-equation-of-state=planetary


Every SPH particle then requires and carries the additional MaterialID flag from the initial conditions file. This flag indicates the particle’s material and which EoS it should use.