Only check the matter content against the cosmology if both cosmology and self...

Only check the matter content against the cosmology if both cosmology and self gravity are activated.

examples/main.c

@@ -718,7 +718,8 @@ int main(int argc, char *argv[]) {
 
     /* Check that the matter content matches the cosmology given in the
      * parameter file. */
-    if (with_cosmology) space_check_cosmology(&s, &cosmo, myrank);
+    if (with_cosmology && with_self_gravity)
+      space_check_cosmology(&s, &cosmo, myrank);
 
 /* Also update the total counts (in case of changes due to replication) */
 #if defined(WITH_MPI)