summaryrefslogtreecommitdiffstats
path: root/examples/h5_read.c
diff options
context:
space:
mode:
Diffstat (limited to 'examples/h5_read.c')
-rw-r--r--examples/h5_read.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/examples/h5_read.c b/examples/h5_read.c
new file mode 100644
index 0000000..99e1801
--- /dev/null
+++ b/examples/h5_read.c
@@ -0,0 +1,128 @@
+/*
+ * This example reads hyperslab from the SDS.h5 file
+ * created by h5_write.c program into two-dimensional
+ * plane of the tree-dimensional array.
+ * Information about dataset in the SDS.h5 file is obtained.
+ */
+
+#include "hdf5.h"
+
+#define FILE "SDS.h5"
+#define DATASETNAME "IntArray"
+#define NX_SUB 3 /* hyperslab dimensions */
+#define NY_SUB 4
+#define NX 7 /* output buffer dimensions */
+#define NY 7
+#define NZ 3
+#define RANK 2
+#define RANK_OUT 3
+
+main ()
+{
+ hid_t file, dataset; /* handles */
+ hid_t datatype, dataspace;
+ hid_t memspace;
+ H5T_class_t class; /* data type class */
+ H5T_order_t order; /* data order */
+ size_t size; /* size of the data element
+ stored in file */
+ size_t dimsm[3]; /* memory space dimensions */
+ size_t dims_out[2]; /* dataset dimensions */
+ herr_t status;
+
+ int data_out[NX][NY][NZ ]; /* output buffer */
+
+ size_t count[2]; /* size of the hyperslab in the file */
+ int offset[2]; /* hyperslab offset in the file */
+ size_t count_out[3]; /* size of the hyperslab in memory */
+ int offset_out[3]; /* hyperslab offset in memory */
+ int i, j, k, status_n, rank;
+
+for (j = 0; j < NX; j++) {
+ for (i = 0; i < NY; i++) {
+ for (k = 0; k < NZ ; k++)
+ data_out[j][i][k] = 0;
+ }
+}
+
+/*
+ * Open the file and the dataset.
+ */
+file = H5Fopen(FILE, H5ACC_DEFAULT, H5C_DEFAULT);
+dataset = H5Dopen(file, DATASETNAME);
+
+/*
+ * Get datatype and dataspace handles and then query
+ * dataset class, order, size, rank and dimensions.
+ */
+
+datatype = H5Dget_type(dataset); /* datatype handle */
+class = H5Tget_class(datatype);
+if (class == H5T_INTEGER) printf("Data set has INTEGER type \n");
+order = H5Tget_order(datatype);
+if (order == H5T_ORDER_LE) printf("Little endian order \n");
+
+size = H5Tget_size(datatype);
+printf(" Data size is %d \n", size);
+
+dataspace = H5Dget_space(dataset); /* dataspace handle */
+rank = H5Pget_ndims(dataspace);
+status_n = H5Pget_dims(dataspace, dims_out);
+printf("rank %d, dimensions %d x %d \n", rank, dims_out[0], dims_out[1]);
+
+/*
+ * Define hyperslab in the datatset.
+ */
+offset[0] = 1;
+offset[1] = 2;
+count[0] = NX_SUB;
+count[1] = NY_SUB;
+status = H5Pset_hyperslab(dataspace, offset, count, NULL);
+
+/*
+ * Define the memory dataspace.
+ */
+dimsm[0] = NX;
+dimsm[1] = NY;
+dimsm[2] = NZ ;
+memspace = H5Pcreate_simple(RANK_OUT,dimsm,NULL);
+
+/*
+ * Define memory hyperslab.
+ */
+offset_out[0] = 3;
+offset_out[1] = 0;
+offset_out[2] = 0;
+count_out[0] = NX_SUB;
+count_out[1] = NY_SUB;
+count_out[2] = 1;
+status = H5Pset_hyperslab(memspace, offset_out, count_out, NULL);
+
+/*
+ * Read data from hyperslab in the file into the hyperslab in
+ * memory and display.
+ */
+status = H5Dread(dataset, H5T_NATIVE_INT, memspace, dataspace,
+ H5C_DEFAULT, data_out);
+for (j = 0; j < NX; j++) {
+ for (i = 0; i < NY; i++) printf("%d ", data_out[j][i][0]);
+ printf("\n");
+}
+ /* 0 0 0 0 0 0 0
+ 0 0 0 0 0 0 0
+ 0 0 0 0 0 0 0
+ 3 4 5 6 0 0 0
+ 4 5 6 7 0 0 0
+ 5 6 7 8 0 0 0
+ 0 0 0 0 0 0 0 */
+
+/*
+ * Close/release resources.
+ */
+H5Tclose(datatype);
+H5Dclose(dataset);
+H5Pclose(dataspace);
+H5Pclose(memspace);
+H5Fclose(file);
+
+}