mirror of
https://github.com/HDFGroup/hdf5.git
synced 2024-11-21 01:04:10 +08:00
154 lines
3.5 KiB
C
154 lines
3.5 KiB
C
/*
|
|
* This example shows how to create a compound data type,
|
|
* write an array which has the compound data type to the file,
|
|
* and read back fields' subsets.
|
|
*/
|
|
|
|
#include "hdf5.h"
|
|
|
|
#define FILE "SDScompound.h5"
|
|
#define DATASETNAME "ArrayOfStructures"
|
|
#define LENGTH 10
|
|
#define RANK 1
|
|
|
|
int
|
|
main(void)
|
|
{
|
|
|
|
/* First structure and dataset*/
|
|
typedef struct s1_t {
|
|
int a;
|
|
float b;
|
|
double c;
|
|
} s1_t;
|
|
s1_t s1[LENGTH];
|
|
hid_t s1_tid; /* File datatype identifier */
|
|
|
|
/* Second structure (subset of s1_t) and dataset*/
|
|
typedef struct s2_t {
|
|
double c;
|
|
int a;
|
|
} s2_t;
|
|
s2_t s2[LENGTH];
|
|
hid_t s2_tid; /* Memory datatype handle */
|
|
|
|
/* Third "structure" ( will be used to read float field of s1) */
|
|
hid_t s3_tid; /* Memory datatype handle */
|
|
float s3[LENGTH];
|
|
|
|
int i;
|
|
hid_t file, dataset, space; /* Handles */
|
|
herr_t status;
|
|
hsize_t dim[] = {LENGTH}; /* Dataspace dimensions */
|
|
|
|
|
|
/*
|
|
* Initialize the data
|
|
*/
|
|
for (i = 0; i< LENGTH; i++) {
|
|
s1[i].a = i;
|
|
s1[i].b = i*i;
|
|
s1[i].c = 1./(i+1);
|
|
}
|
|
|
|
/*
|
|
* Create the data space.
|
|
*/
|
|
space = H5Screate_simple(RANK, dim, NULL);
|
|
|
|
/*
|
|
* Create the file.
|
|
*/
|
|
file = H5Fcreate(FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
|
|
|
|
/*
|
|
* Create the memory data type.
|
|
*/
|
|
s1_tid = H5Tcreate (H5T_COMPOUND, sizeof(s1_t));
|
|
H5Tinsert(s1_tid, "a_name", HOFFSET(s1_t, a), H5T_NATIVE_INT);
|
|
H5Tinsert(s1_tid, "c_name", HOFFSET(s1_t, c), H5T_NATIVE_DOUBLE);
|
|
H5Tinsert(s1_tid, "b_name", HOFFSET(s1_t, b), H5T_NATIVE_FLOAT);
|
|
|
|
/*
|
|
* Create the dataset.
|
|
*/
|
|
dataset = H5Dcreate(file, DATASETNAME, s1_tid, space, H5P_DEFAULT);
|
|
|
|
/*
|
|
* Wtite data to the dataset;
|
|
*/
|
|
status = H5Dwrite(dataset, s1_tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, s1);
|
|
|
|
/*
|
|
* Release resources
|
|
*/
|
|
H5Tclose(s1_tid);
|
|
H5Sclose(space);
|
|
H5Dclose(dataset);
|
|
H5Fclose(file);
|
|
|
|
/*
|
|
* Open the file and the dataset.
|
|
*/
|
|
file = H5Fopen(FILE, H5F_ACC_RDONLY, H5P_DEFAULT);
|
|
|
|
dataset = H5Dopen(file, DATASETNAME);
|
|
|
|
/*
|
|
* Create a data type for s2
|
|
*/
|
|
s2_tid = H5Tcreate(H5T_COMPOUND, sizeof(s2_t));
|
|
|
|
H5Tinsert(s2_tid, "c_name", HOFFSET(s2_t, c), H5T_NATIVE_DOUBLE);
|
|
H5Tinsert(s2_tid, "a_name", HOFFSET(s2_t, a), H5T_NATIVE_INT);
|
|
|
|
/*
|
|
* Read two fields c and a from s1 dataset. Fields in the file
|
|
* are found by their names "c_name" and "a_name".
|
|
*/
|
|
status = H5Dread(dataset, s2_tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, s2);
|
|
|
|
/*
|
|
* Display the fields
|
|
*/
|
|
printf("\n");
|
|
printf("Field c : \n");
|
|
for( i = 0; i < LENGTH; i++) printf("%.4f ", s2[i].c);
|
|
printf("\n");
|
|
|
|
printf("\n");
|
|
printf("Field a : \n");
|
|
for( i = 0; i < LENGTH; i++) printf("%d ", s2[i].a);
|
|
printf("\n");
|
|
|
|
/*
|
|
* Create a data type for s3.
|
|
*/
|
|
s3_tid = H5Tcreate(H5T_COMPOUND, sizeof(float));
|
|
|
|
status = H5Tinsert(s3_tid, "b_name", 0, H5T_NATIVE_FLOAT);
|
|
|
|
/*
|
|
* Read field b from s1 dataset. Field in the file is found by its name.
|
|
*/
|
|
status = H5Dread(dataset, s3_tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, s3);
|
|
|
|
/*
|
|
* Display the field
|
|
*/
|
|
printf("\n");
|
|
printf("Field b : \n");
|
|
for( i = 0; i < LENGTH; i++) printf("%.4f ", s3[i]);
|
|
printf("\n");
|
|
|
|
/*
|
|
* Release resources
|
|
*/
|
|
H5Tclose(s2_tid);
|
|
H5Tclose(s3_tid);
|
|
H5Dclose(dataset);
|
|
H5Fclose(file);
|
|
|
|
return 0;
|
|
}
|