eccodes/examples/F90/grib_set_pv.f90

73 lines
2.0 KiB
Fortran

! (C) Copyright 2005- ECMWF.
!
! This software is licensed under the terms of the Apache Licence Version 2.0
! which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
!
! In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
! virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
!
!
! Description: How to set pv values in a GRIB message
!
!
program grib_set_pv
use eccodes
implicit none
integer :: numberOfLevels
integer :: numberOfCoefficients
integer :: outfile, igrib
integer :: i, ios
real, dimension(:), allocatable :: pv
numberOfLevels = 60
numberOfCoefficients = 2*(numberOfLevels + 1)
allocate (pv(numberOfCoefficients))
! read the model level coefficients from file
open (unit=1, file="../../data/60_model_levels", &
form="formatted", action="read")
do i = 1, numberOfCoefficients, 2
read (unit=1, fmt=*, iostat=ios) pv(i), pv(i + 1)
if (ios /= 0) then
print *, "I/O error: ", ios
exit
end if
end do
! print coefficients
!do i=1,numberOfCoefficients,2
! print *," a=",pv(i)," b=",pv(i+1)
!end do
close (unit=1)
call codes_open_file(outfile, 'out.pv.grib1', 'w')
! A new grib message is loaded from file
! igrib is the grib id to be used in subsequent calls
call codes_grib_new_from_samples(igrib, "reduced_gg_sfc_grib1")
! set levtype to ml (model level)
call codes_set(igrib, 'typeOfLevel', 'hybrid')
! set level
call codes_set(igrib, 'level', 2)
! set PVPresent as an integer
call codes_set(igrib, 'PVPresent', 1)
call codes_set(igrib, 'pv', pv)
! write modified message to a file
call codes_write(igrib, outfile)
! free memory
call codes_release(igrib)
deallocate (pv)
call codes_close_file(outfile)
end program grib_set_pv