!-----------------------------------------------------------------------
      subroutine imf15m (iyr,ndata,date,bx,by,bz,swvel,swden)
!
! Dec 2011 Barbara Emery: imf15m to read yearly netcdf (.nc) file of 15 min
!  OMNI IMF data every 5 min where t=0 uses averages from t=-20 to -5 min
!  (recommended by Daniel Weimer).
!
  include "/opt/local/include/netcdf.inc"

  character*47 omnifile
  integer :: iy4
  real :: missing
  real :: date(ndata),bx(ndata),by(ndata),bz(ndata),swvel(ndata),swden(ndata)

  missing = -9999.		!??? missing value in imf_OMNI 5-min 15min av files
  iy4 = iyr/4
  iend = 365
  if (iyr .eq. iy4*4) iend = 366
  write (omnifile,"('/hao/aim3/tgcm/data/imf_OMNI_',i4,'001-',i4,i3.3,'.nc')") iyr,iyr,iend
      istat = nf_open(omnifile,NF_NOWRITE,ncid)
      if (istat /= NF_NOERR) then
        write(6,"('Error opening imf_ncfile ',a)")trim(omnifile)
        stop
      endif
      write(6,"(/,72('-'))")
      write(6,"('RDIMF: read IMF data file:')")
      write(6,"('Opened netcdf imf data file ',a)") trim(omnifile)

! Get ndata and ndays dimensions:
      istat = nf_inq_dimid(ncid,'ndata',id_ndata)
      istat = nf_inq_dimlen(ncid,id_ndata,ndata)
      write(6,"('rdimf: ndata=',i5)") ndata
!     istat = nf_inq_dimid(ncid,'ndays',id_ndays)
!     istat = nf_inq_dimlen(ncid,id_ndays,ndays)
!     write(6,"('rdimf: ndata=',i5,' ndays=',i5)") ndata,ndays

! Allocate data arrays and initialize structure pointers:
!      call alloc_imf

! yyyyddd.frac date:
      istat = nf_inq_varid(ncid,'date',idv_date)
      istat = nf_get_var_double(ncid,idv_date,date)
      write(6,"('rdimf: date min,max=',2f14.4)") minval(date),maxval(date)

! bx:
      istat = nf_inq_varid(ncid,'bx',idv_bx)
      istat = nf_get_var_double(ncid,idv_bx,bx)
      call fminmaxspv(bx,ndata,fmin,fmax,missing)
      write(6,"('rdimf: bx min,max=',2f8.2)") fmin,fmax

! by:
      istat = nf_inq_varid(ncid,'by',idv_by)
      istat = nf_get_var_double(ncid,idv_by,by)
      call fminmaxspv(by,ndata,fmin,fmax,missing)
      write(6,"('rdimf: by min,max=',2f8.2)") fmin,fmax

! bz:
      istat = nf_inq_varid(ncid,'bz',idv_bz)
      istat = nf_get_var_double(ncid,idv_bz,bz)
      call fminmaxspv(bz,ndata,fmin,fmax,missing)
      write(6,"('rdimf: bz min,max=',2f8.2)") fmin,fmax

! swvel:
      istat = nf_inq_varid(ncid,'swvel',idv_swvel)
      istat = nf_get_var_double(ncid,idv_swvel,swvel)
      call fminmaxspv(swvel,ndata,fmin,fmax,missing)
      write(6,"('rdimf: swvel min,max=',2f8.2)") fmin,fmax

! swden:
      istat = nf_inq_varid(ncid,'swden',idv_swden)
      istat = nf_get_var_double(ncid,idv_swden,swden)
      call fminmaxspv(swden,ndata,fmin,fmax,missing)
      write(6,"('rdimf: swden min,max=',2f8.2)") fmin,fmax


      write(6,"(72('-'),/)")
      end subroutine imf15m
!-----------------------------------------------------------------------
!      subroutine alloc_imf

! real,dimension(:),target,allocatable ::
!   uttime,yfrac,bx,by,bz,swvel,swden,kp,f107d,f107a

!      integer :: istat
!      allocate(date(ndata),stat=istat)
!      allocate(uttime(ndata),stat=istat)
!      allocate(yfrac(ndata),stat=istat)
!      allocate(bx(ndata),stat=istat)
!      allocate(by(ndata),stat=istat)
!      allocate(bz(ndata),stat=istat)
!      allocate(swvel(ndata),stat=istat)
!      allocate(swden(ndata),stat=istat)
!      allocate(kp(ndata),stat=istat)

!     allocate(days(ndays),stat=istat)
!     allocate(f107d(ndays),stat=istat)
!     allocate(f107a(ndays),stat=istat)

!      end subroutine alloc_imf
!-----------------------------------------------------------------------
      subroutine fminmaxspv(f,n,fmin,fmax,spv)
      implicit none
!
! Return min and max of fields f(n) (between -1.e36,+1.e36)
! Ignore any f(i)==spv.
!
! Args:
      integer,intent(in) :: n
      real,intent(in) :: f(n),spv
      real,intent(out) :: fmin,fmax
!
! Local:
      integer :: i
!
      fmin = 1.e36
      fmax = -1.e36
      do i=1,n
        if (f(i) /= spv) then
          fmin = min(f(i),fmin)
          fmax = max(f(i),fmax)
        endif
      enddo
      end subroutine fminmaxspv
!-------------------------------------------------------------------