00001 ! Copyright 2005-2017 ECMWF
00002 ! This software is licensed under the terms of the Apache Licence Version 2.0
00003 ! which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
00004 !
00005 ! In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
00006 ! virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
00007 !
00008 !
00009 ! Description: how to use grib_find_nearest and grib_get_element
00010 !
00011 !
00012 ! Author: Enrico Fucile
00013 !
00014 !
00015 !
00016 program find
00017 use grib_api
00018 implicit none
00019 integer :: npoints
00020 integer :: infile
00021 integer :: igrib, ios, i
00022 real(8), dimension(:), allocatable :: lats, lons
00023 real(8), dimension(:), allocatable :: nearest_lats, nearest_lons
00024 real(8), dimension(:), allocatable :: distances, values, lsm_values
00025 integer(kind=kindOfInt), dimension(:), allocatable :: indexes
00026 real(kind=8) :: value
00027
00028 ! initialization
00029 open( unit=1, file="../../data/list_points",form="formatted",action="read")
00030 read(unit=1,fmt=*) npoints
00031 allocate(lats(npoints))
00032 allocate(lons(npoints))
00033 allocate(nearest_lats(npoints))
00034 allocate(nearest_lons(npoints))
00035 allocate(distances(npoints))
00036 allocate(lsm_values(npoints))
00037 allocate(values(npoints))
00038 allocate(indexes(npoints))
00039 do i=1,npoints
00040 read(unit=1,fmt=*, iostat=ios) lats(i), lons(i)
00041 if (ios /= 0) then
00042 npoints = i - 1
00043 exit
00044 end if
00045 end do
00046 close(unit=1)
00047 call grib_open_file(infile, &
00048 '../../data/reduced_gaussian_lsm.grib1','r')
00049
00050 ! a new grib message is loaded from file
00051 ! igrib is the grib id to be used in subsequent calls
00052 call grib_new_from_file(infile,igrib)
00053
00054
00055 call grib_find_nearest(igrib, .true., lats, lons, nearest_lats, nearest_lons,lsm_values, distances, indexes)
00056 call grib_release(igrib)
00057
00058 call grib_close_file(infile)
00059
00060 ! will apply it to another GRIB
00061 call grib_open_file(infile, &
00062 '../../data/reduced_gaussian_pressure_level.grib1','r')
00063 call grib_new_from_file(infile,igrib)
00064
00065 call grib_get_element(igrib,"values", indexes, values)
00066 call grib_release(igrib)
00067 call grib_close_file(infile)
00068
00069 do i=1, npoints
00070 print*,lats(i), lons(i), nearest_lats(i), nearest_lons(i), distances(i), lsm_values(i), values(i)
00071 end do
00072
00073 deallocate(lats)
00074 deallocate(lons)
00075 deallocate(nearest_lats)
00076 deallocate(nearest_lons)
00077 deallocate(distances)
00078 deallocate(lsm_values)
00079 deallocate(values)
00080 deallocate(indexes)
00081
00082 end program find
