Added more explicit cosmological conversion factors to the cosmology structure.

src/cosmology.c

@@ -138,6 +138,9 @@ void cosmology_update(struct cosmology *c, integertime_t ti_current) {
   c->a_inv = a_inv;
   c->a2_inv = a_inv * a_inv;
   c->a3_inv = a_inv * a_inv * a_inv;
+  c->a_factor_internal_energy =
+      pow(a, -3. * hydro_gamma_minus_one);          /* a^{3*(1-gamma)} */
+  c->a_factor_pressure = pow(a, -3. * hydro_gamma); /* a^{-3*gamma} */
   c->a_factor_sound_speed =
       pow(a, -1.5 * hydro_gamma_minus_one); /* a^{3*(1-gamma)/2} */
   c->a_factor_grav_accel = a_inv * a_inv;   /* 1 / a^2 */
@@ -459,6 +462,8 @@ void cosmology_init_no_cosmo(struct cosmology *c) {
   c->a_inv = 1.;
   c->a2_inv = 1.;
   c->a3_inv = 1.;
+  c->a_factor_internal_energy = 1.;
+  c->a_factor_pressure = 1.;
   c->a_factor_sound_speed = 1.;
   c->a_factor_mu = 1.;
   c->a_factor_hydro_accel = 1.;

src/cosmology.h

@@ -44,10 +44,18 @@ struct cosmology {
   /*! Inverse cube of the current expansion factor of the Universe */
   double a3_inv;
 
-  /*! Power of the scale-factor used for sound-speed conversion */
+  /*! Power of the scale-factor used for internal energy conversion to physical
+   */
+  double a_factor_internal_energy;
+
+  /*! Power of the scale-factor used for pressure conversion to physical */
+  double a_factor_pressure;
+
+  /*! Power of the scale-factor used for sound-speed conversion to physical */
   double a_factor_sound_speed;
 
-  /*! Power of the scale-factor used for relative velocities in viscosity ter */
+  /*! Power of the scale-factor used for relative velocities in viscosity term
+   */
   double a_factor_mu;
 
   /*! Power of the scale-factor used for gravity accelerations */