## Function Gamma-Ln

(

**gamma-ln** < x > )

Returns the natural logarithm of the Gamma function evaluated at ` x.'<br> Mathematically, the Gamma function is defined to be the integral from 0 to<br> Infinity of t^x exp(-t) dt. The implementation is copied, with extensions for<br> the reflection formula, from Numerical Recipes in C, section 6.1. The argument<br>`

x' must be positive. Full accuracy is obtained for x>1. For x<1, the

reflection formula is used. The computation is done using double-floats, and

the result is a double-float.