* Using mathematical intrinsic functions.
    
      program intrinsics
      
      real x, pi, e      
      parameter ( pi = 3.141592653589793 )                      
      parameter (  e = 2.718281828459045 )

      write (*, *) '--- abs ---'
      x = abs(3 * -5)
      write (*, *) x
      x = abs(x / 2)
      write (*, *) x
      x = abs(15 / -2)
      write (*, *) x

      write (*, *) '--- min ---'
      x = min(12 * -0.5, (-2) ** 3)
      write (*, *) x      
      x = min(-2 ** 3, -3 ** 2)
      write (*, *) x
      x = min(2 ** 3, 3 ** 2)
      write (*, *) x

      write (*, *) '--- max ---'
      x = max(12 * -0.5, (-2) ** 3)
      write (*, *) x      
      x = max(-2 ** 3, -3 ** 2)
      write (*, *) x
      x = max(2 ** 3, 3 ** 2)
      write (*, *) x

      write (*, *) '--- sqrt ---'
      x = sqrt(4 * 0.5)
      write (*, *) x      
      x = sqrt(10.0 ** 2 ** 1)
      write (*, *) x
      x = sqrt(1 - 10.0)
      write (*, *) x

      write (*, *) '--- sin ---'
      x = sin(0.0)
      write (*, *) x
      x = sin(pi / 6)
      write (*, *) x      
      x = sin(pi / 2)
      write (*, *) x

      write (*, *) '--- cos ---'
      x = cos(0.0)
      write (*, *) x
      x = cos(pi / 3)
      write (*, *) x      
      x = cos(pi / 2)
      write (*, *) x

      write (*, *) '--- tan ---'
      x = tan(0.0)
      write (*, *) x
      x = tan(pi / 4)
      write (*, *) x      
      x = tan(pi / 6)
      write (*, *) x

      write (*, *) '--- atan ---'
      x = atan(0.0)
      write (*, *) x
      x = atan(sqrt(5.1 - 2.1))
      write (*, *) x
      x = atan(42 ** 0.0)
      write (*, *) x

      write (*, *) '--- exp ---'
      x = exp(x - x)
      write (*, *) x
      x = exp(x)
      write (*, *) x
      x = exp(2.0 ** 10)
      write (*, *) x

      write (*, *) '--- log ---'
      x = log(e ** 0)
      write (*, *) x
      x = log(e)
      write (*, *) x
      x = log(1024.0) / log(2.0)
      write (*, *) x

      stop
      end