subroutine cpt(ave,std,csm,xlo,xhi,xin)

c - 2016 09 06
c   Modified because the forcing of "scave" to be one non zero
c   digit was throwing off the scalebar so far in Guam that
c   the data in Guam wasn't even plotting.  Change to make
c   the interval still be one non zero digit, but then a 
c   simpler formula for the scaled average was put in.

c - 2016 07 29
c   Modified from original version to reflect "new math" invented
c   this week that helps shrink the color bar and/or widen the
c   color bar (see issues 14 and 15 in DRU-12, p. 48)

      implicit none
      real*8 ave,std,csm,xlo,xhi,xin
      real*8 qv,qq,scave
      integer*4 iv,iq
      real*8 spread8,onzd2
c - This subroutine generates the color pallette variables
c - for a GMT color plot
c
c - Input:
c    ave = Average of the gridded data
c    std = Standard deviation of the gridded data
c    csm = Color Sigma Multiplier (how many sigmas on each
c          side of the average do you want the colors to range?)
c - Output:
c    xlo = Low value
c    xhi = High value
c    xin = Interval

      spread8 = 2 * csm * std / 8.d0
      xin = onzd2(spread8) 

c     iv = floor(dlog10(std))
c     qv = 10.d0**iv
c     qq = std / qv
c     iq = nint(qq)

c - 2016 09 06
c     write(6,*) ' cpt: ave (pre  onzd2) = ',ave
c     scave = onzd2(ave)
c     write(6,*) ' cpt: ave (post onzd2) = ',ave
      scave = xin * nint(ave / xin)

c     xin = iq * qv
c     scave = qv * nint(ave/qv)

c     xlo = scave - csm*xin
c     xhi = scave + csm*xin

      xlo = scave - 4*xin
      xhi = scave + 4*xin

      write(6,101)ave,std,csm,spread8,ave-csm*std,ave+csm*std,
     *xin,scave,xlo,xhi
  101 format(15('-'),/,
     *12x,'Inside cpt.f',/,
     *12x,'    cpt.f: ave      = ',f18.6,/,
     *12x,'    cpt.f: std      = ',f18.6,/,
     *12x,'    cpt.f: csm      = ',f18.6,/,
     *12x,'    cpt.f: spread8  = ',f18.6,/,
     *12x,'    cpt.f: targ low = ',f18.6,/,
     *12x,'    cpt.f: targ high= ',f18.6,//
     *12x,'    cpt.f: xin      = ',f18.6,/,
     *12x,'    cpt.f: scave    = ',f18.6,/,
     *12x,'    cpt.f: xlo      = ',f18.6,/,
     *12x,'    cpt.f: xhi      = ',f18.6,/,
     *15('-'))

      return
      end
      include '/home/dru/Subs/onzd2.f'