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author | Elena Pourmal <epourmal@hdfgroup.org> | 1998-08-31 21:36:28 (GMT) |
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committer | Elena Pourmal <epourmal@hdfgroup.org> | 1998-08-31 21:36:28 (GMT) |
commit | 65dea75ab8146583a30bd2b84e4b2202a2afe438 (patch) | |
tree | d9ac01ff31e5c89eb907e9e59b19ff9f9c2cb42e /examples/h5_attribute.c | |
parent | 0d7ec99e1dbcaafa8c39495df555acd7b7ad63bb (diff) | |
download | hdf5-65dea75ab8146583a30bd2b84e4b2202a2afe438.zip hdf5-65dea75ab8146583a30bd2b84e4b2202a2afe438.tar.gz hdf5-65dea75ab8146583a30bd2b84e4b2202a2afe438.tar.bz2 |
[svn-r639] Two new examples h5_select.c and h5_attribute.c were added to the directory.
Makefile.in was modified to reflect those changes.
Tested on Sun Sparc ( baldric) and DEC Alpha (gondolin)
Diffstat (limited to 'examples/h5_attribute.c')
-rw-r--r-- | examples/h5_attribute.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/examples/h5_attribute.c b/examples/h5_attribute.c new file mode 100644 index 0000000..661f72d --- /dev/null +++ b/examples/h5_attribute.c @@ -0,0 +1,259 @@ +/* + * This program illustrates the usage of the H5A Interface functions. + * It creates and writes a dataset, and then creates and writes array, + * scalar, and string attributes of the dataset. + * Program reopens the file, attaches to the scalar attribute using + * attribute name and reads and displays its value. Then index of the + * third attribute is used to read and display attribute values. + * The H5Aiterate function is used to iterate through the dataset attributes, + * and display their names. The function is also reads and displays the values + * of the array attribute. + */ + +#include <hdf5.h> + +#define FILE "Attributes.h5" + +#define RANK 1 /* Rank and size of the dataset */ +#define SIZE 7 + +#define ARANK 2 /* Rank and dimension sizes of the first dataset attribute */ +#define ADIM1 2 +#define ADIM2 3 +#define ANAME "Float attribute" /* Name of the array attribute */ +#define ANAMES "Character attribute" /* Name of the string attribute */ + +herr_t attr_info(hid_t loc_id, const char *name, void *opdata); + /* Operator function */ + +int main (void) +{ + + hid_t file, dataset; /* File and dataset identifiers */ + + hid_t fid; /* Dataspace identifier */ + hid_t attr1, attr2, attr3; /* Attribute identifiers */ + hid_t attr; + hid_t aid1, aid2, aid3; /* Attribute dataspace identifiers */ + hid_t atype; /* Attribute type */ + + hsize_t fdim[] = {SIZE}; + hsize_t adim[] = {ADIM1, ADIM2}; /* Dimensions of the first attribute */ + + float matrix[ADIM1][ADIM2]; /* Attribute data */ + + herr_t ret; /* Return value */ + uint i,j; /* Counters */ + int idx; /* Attribute index */ + char string_out[80]; /* Buffer to read string attribute back */ + int point_out; /* Buffer to read scalar attribute back */ + +/* + * Data initialization. + */ +int vector[] = {1, 2, 3, 4, 5, 6, 7}; /* Dataset data */ +int point = 1; /* Value of the scalar attribute */ +char string[] = "ABCD"; /* Value of the string attribute */ + + +for (i=0; i < ADIM1; i++) { /* Values of the array attribute */ + for (j=0; j < ADIM2; j++) + matrix[i][j] = -1.; +} + +/* + * Create a file. + */ +file = H5Fcreate(FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT); + +/* + * Create the dataspace for the dataset in the file. + */ +fid = H5Screate(H5S_SIMPLE); +ret = H5Sset_extent_simple(fid, RANK, fdim, NULL); + +/* + * Create the dataset in the file. + */ +dataset = H5Dcreate(file, "Dataset", H5T_NATIVE_INT, fid, H5P_DEFAULT); + +/* + * Write data to the dataset. + */ +ret = H5Dwrite(dataset, H5T_NATIVE_INT, H5S_ALL , H5S_ALL, H5P_DEFAULT, vector); + +/* + * Create dataspace for the first attribute. + */ +aid1 = H5Screate(H5S_SIMPLE); +ret = H5Sset_extent_simple(aid1, ARANK, adim, NULL); + +/* + * Create array attribute. + */ +attr1 = H5Acreate(dataset, ANAME, H5T_NATIVE_FLOAT, aid1, H5P_DEFAULT); + +/* + * Write array attribute. + */ +ret = H5Awrite(attr1, H5T_NATIVE_FLOAT, matrix); + +/* + * Create scalar attribute. + */ +aid2 = H5Screate(H5S_SCALAR); +attr2 = H5Acreate(dataset, "Integer attribute", H5T_NATIVE_INT, aid2, + H5P_DEFAULT); + +/* + * Write scalar attribute. + */ +ret = H5Awrite(attr2, H5T_NATIVE_INT, &point); + +/* + * Create string attribute. + */ +aid3 = H5Screate(H5S_SCALAR); +atype = H5Tcopy(H5T_C_S1); + H5Tset_size(atype, 4); +attr3 = H5Acreate(dataset, ANAMES, atype, aid3, H5P_DEFAULT); + +/* + * Write string attribute. + */ +ret = H5Awrite(attr3, atype, string); + +/* + * Close attribute and file datapsaces. + */ +ret = H5Sclose(aid1); +ret = H5Sclose(aid2); +ret = H5Sclose(aid3); +ret = H5Sclose(fid); + +/* + * Close the attributes. + */ +ret = H5Aclose(attr1); +ret = H5Aclose(attr2); +ret = H5Aclose(attr3); + +/* + * Close the dataset. + */ +ret = H5Dclose(dataset); + +/* + * Close the file. + */ +ret = H5Fclose(file); + +/* + * Reopen the file. + */ +file = H5Fopen(FILE, H5F_ACC_RDONLY, H5P_DEFAULT); + +/* + * Open the dataset. + */ +dataset = H5Dopen(file,"Dataset"); + +/* + * Attach to the scalar attribute using attribute name, then read and + * display its value. + */ +attr = H5Aopen_name(dataset,"Integer attribute"); +ret = H5Aread(attr, H5T_NATIVE_INT, &point_out); +printf("The value of the attribute \"Integer attribute\" is %d \n", point_out); +ret = H5Aclose(attr); + +/* + * Attach to the string attribute using its index, then read and display the value. + */ +attr = H5Aopen_idx(dataset, 2); +atype = H5Tcopy(H5T_C_S1); + H5Tset_size(atype, 4); +ret = H5Aread(attr, atype, string_out); +printf("The value of the attribute with the index 2 is %s \n", string_out); +ret = H5Aclose(attr); +ret = H5Tclose(atype); + +/* + * Get attribute info using iteration function. + */ +idx = H5Aiterate(dataset, NULL, attr_info, NULL); + +/* + * Close the dataset and the file. + */ +H5Dclose(dataset); +H5Fclose(file); +return 0; +} + +/* + * Operator function. + */ +herr_t attr_info(hid_t loc_id, const char *name, void *opdata) +{ + hid_t attr, atype, aspace; /* Attribute, datatype and dataspace identifiers */ + int rank; + hsize_t sdim[64]; + herr_t ret; + int i; + size_t npoints; /* Number of elements in the array attribute. */ + float *float_array; /* Pointer to the array attribute. */ +/* + * Open the attribute using its name. + */ + attr = H5Aopen_name(loc_id, name); + +/* + * Display attribute name. + */ + printf("\n"); + printf("Name : "); + puts(name); + +/* + * Get attribute datatype, dataspace, rank, and dimensions. + */ + atype = H5Aget_type(attr); + aspace = H5Aget_space(attr); + rank = H5Sextent_ndims(aspace); + ret = H5Sextent_dims(aspace, sdim, NULL); +/* + * Display rank and dimension sizes for the array attribute. + */ + + if(rank > 0) { + printf("Rank : %d \n", rank); + printf("Dimension sizes : "); + for (i=0; i< rank; i++) printf("%d ", (int)sdim[i]); + printf("\n"); + } + +/* + * Read array attribute and display its type and values. + */ + + if (H5T_FLOAT == H5Tget_class(atype)) { + printf("Type : FLOAT \n"); + npoints = H5Sextent_npoints(aspace); + float_array = (float *)malloc(sizeof(float)*(int)npoints); + ret = H5Aread(attr, atype, float_array); + printf("Values : "); + for( i = 0; i < npoints; i++) printf("%f ", float_array[i]); + printf("\n"); + free(float_array); + } + + +/* + * Release all identifiers. + */ + H5Tclose(atype); + H5Sclose(aspace); + H5Aclose(attr); + return 0; +} |