Hello, I've been using mpf_class and mpf_t in some numerical programs where the results do not fit into doubles. All was well until it was required to take the exponential of an mpf_t. Specifically, I've been using GNU GSL with GNU GMP. Calling gsl_sf_exp() on a mpf_t that has been converted to a double results in an overflow. I'd appreciate help in solving this problem. I looked to see if there was an arbitrary power function to a float for GMP, but didn't see one listed in the documentation. I'd appreciate any possible solutions for this problem. GMP has solved many of my large number problems, but this last issue remains. Thanks,   Marc.