BOOST_MATH_INSTRUMENT_VARIABLE(guess);
if(guess == lower)
guess = policies::raise_underflow_error<T>(function, "Expected result known to be non-zero, but is smaller than the smallest available number.", pol);
BOOST_MATH_INSTRUMENT_VARIABLE(guess);
if(guess == lower)
guess = policies::raise_underflow_error<T>(function, "Expected result known to be non-zero, but is smaller than the smallest available number.", pol);