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38581db0c   daniau   git-svn-id: https... 
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        complex(8) function z9lgmc (zin)
        implicit none
  c april 1978 edition.  w. fullerton c3, los alamos scientific lab.
  c
  c compute the log gamma correction term for large cabs(z) when real(z)
  c .ge. 0.0 and for large abs(aimag(y)) when real(z) .lt. 0.0.  we find
  c c9lgmc so that
  c   clog(cgamma(z)) = 0.5*alog(2.*pi) + (z-0.5)*clog(z) - z + c9lgmc(z).
  c
        complex(8) zin, z, z2inv
        real(8) d1mach,bern,xbig,xmax,bound,cabsz,x,y
        integer nterm,i,ndx
        external d1mach
  c
        dimension bern(11)
        data bern( 1) /    .08333333333 3333333e0   /
        data bern( 2) /   -.002777777777 7777778e0  /
        data bern( 3) /    .0007936507936 5079365e0 /
        data bern( 4) /   -.0005952380952 3809524e0 /
        data bern( 5) /    .0008417508417 5084175e0 /
        data bern( 6) /   -.001917526917 5269175e0  /
        data bern( 7) /    .006410256410 2564103e0  /
        data bern( 8) /   -.02955065359 4771242e0   /
        data bern( 9) /    .1796443723 6883057e0    /
        data bern(10) /  -1.392432216 9059011e0     /
        data bern(11) /  13.40286404 4168392e0      /
  c
        data nterm, bound, xbig, xmax / 0, 3*0.0 /
  c
        if (nterm.ne.0) go to 10
  c
        nterm = -0.30*log(d1mach(3))
        bound = 0.1170*dble(nterm)*
       1  (0.1*d1mach(3))**(-1./(2.*dble(nterm)-1.))
        xbig = 1.0/sqrt(d1mach(3))
        xmax = exp (min(log(d1mach(2)/12.0), -log(12.*d1mach(1))) )
  c
   10   z = zin
        x = real (z)
        y = aimag(z)
        cabsz = abs(z)
  c
        if (x.lt.0.0 .and. abs(y).lt.bound) call seteru ( 69hc9lgmc  c9lgm
       1c not valid for negative real(z) and small abs(aimag(z)), 69, 2,2)
        if (cabsz.lt.bound) call seteru (
       1  42hz9lgmc  z9lgmc not valid for small cabs(z), 42, 3, 2)
  c
        if (cabsz.ge.xmax) go to 50
  c
        if (cabsz.ge.xbig) z9lgmc = 1.0/(12.0*z)
        if (cabsz.ge.xbig) return
  c
        z2inv = 1.0/z**2
        z9lgmc = (0.0, 0.0)
        do 40 i=1,nterm
          ndx = nterm + 1 - i
          z9lgmc = bern(ndx) + z9lgmc*z2inv
   40   continue
  c
        z9lgmc = z9lgmc/z
        return
  c
   50   z9lgmc = (0.0, 0.0)
        call seteru (34hz9lgmc  z so big z9lgmc underflows, 34, 1, 0)
        return
  c
        end