# usecases/c/UsesCase_MEDfield_1.c

    /*  This file is part of MED.
     *
     *  COPYRIGHT (C) 1999 - 2012  EDF R&D, CEA/DEN
     *  MED is free software: you can redistribute it and/or modify
     *  it under the terms of the GNU Lesser General Public License as published by
     *  the Free Software Foundation, either version 3 of the License, or
     *  (at your option) any later version.
     *
     *  MED is distributed in the hope that it will be useful,
     *  but WITHOUT ANY WARRANTY; without even the implied warranty of
     *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     *  GNU Lesser General Public License for more details.
     *
     *  You should have received a copy of the GNU Lesser General Public License
     *  along with MED.  If not, see <http://www.gnu.org/licenses/>.
     */

    /*
     * Field use case 1 : write a field on mesh vertices and elements
     */

    #include <med.h>
    #define MESGERR 1
    #include <med_utils.h>

    #include <string.h>

    int main (int argc, char **argv) {
      med_idt fid;
      const char meshname[MED_NAME_SIZE+1] = "2D unstructured mesh";
      const char fieldname[MED_NAME_SIZE+1] = "TEMPERATURE_FIELD";
      const med_int ncomponent = 1;
      const char componentname[MED_SNAME_SIZE+1] = "TEMPERATURE";
      const char componentunit[MED_SNAME_SIZE+1] = "C";
      const med_float verticesvalues[15] = {  0.,   100., 200.,  300.,  400.,
                                              500.,   600., 700.,  800.,  900,
                                              1000., 1100, 1200., 1300., 1500. };
      const med_int nnodes = 15;
      const med_float tria3values[8] = {1000., 2000., 3000., 4000.,
                                        5000., 6000., 7000., 8000.};
      const med_int ntria3 = 8;
      const med_float quad4values[4] = {10000., 20000., 30000., 4000.};
      const med_int nquad4 = 4;
      int ret=-1;

      /* file creation */
      fid = MEDfileOpen("UsesCase_MEDfield_1.med",MED_ACC_CREAT);
      if (fid < 0) {
        MESSAGE("ERROR : file creation ...");
        goto ERROR;
      }

      /* field creation : temperature field  : 1 component in celsius degree
       *                  the mesh is the 2D unstructured mesh of UsecaseMEDmesh_1.c
       */

      /* create mesh link */
      if (MEDlinkWr(fid,meshname,"./UsesCase_MEDmesh_1.med") < 0) {
        MESSAGE("ERROR : create mesh link ...");
        goto ERROR;
      }

      if (MEDfieldCr(fid, fieldname, MED_FLOAT64,
                     ncomponent, componentname, componentunit,"",
                     meshname) < 0) {
        MESSAGE("ERROR : create field");
        goto ERROR;
      }

      /* write field values at vertices */
      if (MEDfieldValueWr(fid, fieldname, MED_NO_DT, MED_NO_IT, 0.0, MED_NODE,
                          MED_NONE, MED_FULL_INTERLACE, MED_ALL_CONSTITUENT,
                          nnodes,(unsigned char*) verticesvalues) < 0) {
        MESSAGE("ERROR : write field values on vertices");
        goto ERROR;
      }

      /* write values at cell centers : 8 MED_TRIA3 and 4 MED_QUAD4 */
      /* MED_TRIA3 */
      if (MEDfieldValueWr(fid, fieldname, MED_NO_DT, MED_NO_IT, 0.0, MED_CELL,
                          MED_TRIA3, MED_FULL_INTERLACE, MED_ALL_CONSTITUENT,
                          ntria3, (unsigned char*) tria3values) < 0) {
        MESSAGE("ERROR : write field values on MED_TRIA3");
        goto ERROR;
      }
      /* MED_QUAD4 */
      if (MEDfieldValueWr(fid, fieldname, MED_NO_DT, MED_NO_IT, 0.0, MED_CELL,
                          MED_QUAD4, MED_FULL_INTERLACE, MED_ALL_CONSTITUENT,
                          nquad4, (unsigned char*) quad4values) < 0) {
        MESSAGE("ERROR : write field values on MED_QUAD4 ");
        goto ERROR;
      }

      ret=0;
     ERROR :

      /* close file */
      if (MEDfileClose(fid) < 0) {
        MESSAGE("ERROR : close file ...");
        ret = -1;
      }

      return ret;
    }