lgamma, dlgamma (3f)

returns the log of the gamma function

Syntax

  real*4 lgamma, x, r
  external lgamma
  r = lgamma ( x )

  real*8 dlgamma, dx, d
  external dlgamma
  d = dlgamma ( dx )

Description

  The lgamma function returns the natural logarithm of the Gamma function of
  x defined as follows:

      log base e of the integral from 0 to infinity of u to the x-1
      power times e to the -u power du

  The dlgamma function is the double-precision version of lgamma.

See Also

  lgamma(3)