Appropriate c for arbitrary isotropic big bang cosmology. You may use this program for c personal, educational or research purposes.
Commercial purposes require c special arrangements.
If you publish a paper that depends upon this code, c please cite it appropriately. The overdense expansion factor is defined c to be 1 at maximum. In the case where c there is one real root, this routine returns it. If there are three c roots, it returns the smallest positive one. The expansion parameter is defined to c be 1 at turnaround.