hdf5/hl/examples/ex_table_04.c

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * terms governing use, modification, and redistribution, is contained in    *
 * the COPYING file, which can be found at the root of the source code       *
 * distribution tree, or in https://www.hdfgroup.org/licenses.               *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "hdf5.h"
#include "hdf5_hl.h"
#include <stdlib.h>

/*-------------------------------------------------------------------------
 * Table API example
 *
 * H5TBwrite_fields_name
 *
 *-------------------------------------------------------------------------
 */

#define NFIELDS      (hsize_t)5
#define NRECORDS     (hsize_t)8
#define NRECORDS_ADD (hsize_t)3
#define TABLE_NAME   "table"

int
main(void)
{
    typedef struct Particle {
        char   name[16];
        int    lati;
        int    longi;
        float  pressure;
        double temperature;
    } Particle;

    /* Define a subset of Particle, with latitude and longitude fields */
    typedef struct Position {
        int lati;
        int longi;
    } Position;

    /* Define a subset of Particle, with name and pressure fields */
    typedef struct NamePressure {
        char  name[16];
        float pressure;
    } NamePressure;

    Particle dst_buf[NRECORDS];
    /* Calculate the size and the offsets of our struct members in memory */
    size_t dst_size            = sizeof(Particle);
    size_t dst_offset[NFIELDS] = {HOFFSET(Particle, name), HOFFSET(Particle, lati), HOFFSET(Particle, longi),
                                  HOFFSET(Particle, pressure), HOFFSET(Particle, temperature)};
    size_t dst_sizes[NFIELDS]  = {sizeof(dst_buf[0].name), sizeof(dst_buf[0].lati), sizeof(dst_buf[0].longi),
                                 sizeof(dst_buf[0].pressure), sizeof(dst_buf[0].temperature)};
    size_t field_offset_pos[2] = {HOFFSET(Position, lati), HOFFSET(Position, longi)};
    const char *field_names[NFIELDS] = /* Define field information */
        {"Name", "Latitude", "Longitude", "Pressure", "Temperature"};
    hid_t     field_type[NFIELDS];
    hid_t     string_type;
    hid_t     file_id;
    hsize_t   chunk_size   = 10;
    Particle  fill_data[1] = {{"no data", -1, -1, -99.0F, -99.0}}; /* Fill value particle */
    hsize_t   start;                                               /* Record to start reading/writing */
    hsize_t   nrecords;                                            /* Number of records to read/write */
    int       compress = 0;
    int       i;
    Particle *p_data                    = NULL; /* Initially no data */
    float     pressure_in[NRECORDS_ADD] =       /* Define new values for the field "Pressure"  */
        {0.0F, 1.0F, 2.0F};
    Position     position_in[NRECORDS_ADD] = {/* Define new values for "Latitude,Longitude"  */
                                          {0, 0},
                                          {10, 10},
                                          {20, 20}};
    NamePressure namepre_in[NRECORDS_ADD]  = /* Define new values for "Name,Pressure"  */
        {
            {"zero", 0.0F},
            {"one", 1.0F},
            {"two", 2.0F},
        };
    size_t field_sizes_pos[2] = {sizeof(position_in[0].longi), sizeof(position_in[0].lati)};
    size_t field_sizes_pre[1] = {sizeof(namepre_in[0].pressure)};

    /* Initialize the field field_type */
    string_type = H5Tcopy(H5T_C_S1);
    H5Tset_size(string_type, 16);
    field_type[0] = string_type;
    field_type[1] = H5T_NATIVE_INT;
    field_type[2] = H5T_NATIVE_INT;
    field_type[3] = H5T_NATIVE_FLOAT;
    field_type[4] = H5T_NATIVE_DOUBLE;

    /* Create a new file using default properties. */
    file_id = H5Fcreate("ex_table_04.h5", H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    /* Make the table */
    H5TBmake_table("Table Title", file_id, TABLE_NAME, NFIELDS, NRECORDS, dst_size, field_names, dst_offset,
                   field_type, chunk_size, fill_data, compress, p_data);

    /* Write the pressure field starting at record 2 */
    start    = 2;
    nrecords = NRECORDS_ADD;
    H5TBwrite_fields_name(file_id, TABLE_NAME, "Pressure", start, nrecords, sizeof(float), 0, field_sizes_pre,
                          pressure_in);

    /* Write the new longitude and latitude information starting at record 2 */
    start    = 2;
    nrecords = NRECORDS_ADD;
    H5TBwrite_fields_name(file_id, TABLE_NAME, "Latitude,Longitude", start, nrecords, sizeof(Position),
                          field_offset_pos, field_sizes_pos, position_in);

    /* read the table */
    H5TBread_table(file_id, TABLE_NAME, dst_size, dst_offset, dst_sizes, dst_buf);

    /* print it by rows */
    for (i = 0; i < NRECORDS; i++) {
        printf("%-5s %-5d %-5d %-5f %-5f", dst_buf[i].name, dst_buf[i].lati, dst_buf[i].longi,
               dst_buf[i].pressure, dst_buf[i].temperature);
        printf("\n");
    }

    /*-------------------------------------------------------------------------
     * end
     *-------------------------------------------------------------------------
     */

    /* close type */
    H5Tclose(string_type);

    /* close the file */
    H5Fclose(file_id);

    return 0;
}