function ali (x)
  c august 1980 edition.   w. fullerton, c3, los alamos scientific lab.
  c
        external  ei, r1mach
        data sqeps / 0.0 /
  c
        if (sqeps.eq.0.0) sqeps = sqrt(r1mach(3))
        if (x.le.0.0) call seteru (
       1  41hali     log integral undefined for x le 0, 41, 2, 2)
        if (x.eq.1.0) call seteru (
       1  40hali     log integral undefined for x = 1, 40, 3, 2)
        if (abs(1.0-x).lt.sqeps) call seteru (57hali     answer lt half pr
       1ecision because x too close to 1, 57, 1, 1)
  c
        ali = ei (alog(x) )
  c
        return
        end