Proper name for entropy variable in Gadget-2 output

src/hydro/Gadget2/hydro_io.h

@@ -83,7 +83,7 @@ __attribute__((always_inline)) INLINE static void hydro_write_particles(
   writeArray(h_grp, fileName, xmfFile, partTypeGroupName, "SmoothingLength",
              FLOAT, N, 1, parts, N_total, mpi_rank, offset, h, us,
              UNIT_CONV_LENGTH);
-  writeArray(h_grp, fileName, xmfFile, partTypeGroupName, "InternalEnergy",
+  writeArray(h_grp, fileName, xmfFile, partTypeGroupName, "Entropy",
              FLOAT, N, 1, parts, N_total, mpi_rank, offset, entropy, us,
              UNIT_CONV_ENTROPY_PER_UNIT_MASS);
   writeArray(h_grp, fileName, xmfFile, partTypeGroupName, "ParticleIDs",