diff options
Diffstat (limited to 'HDF5Examples/C/H5D/h5ex_d_unlimadd.c')
| -rw-r--r-- | HDF5Examples/C/H5D/h5ex_d_unlimadd.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/HDF5Examples/C/H5D/h5ex_d_unlimadd.c b/HDF5Examples/C/H5D/h5ex_d_unlimadd.c new file mode 100644 index 0000000..c0d23e4 --- /dev/null +++ b/HDF5Examples/C/H5D/h5ex_d_unlimadd.c @@ -0,0 +1,237 @@ +/************************************************************ + + This example shows how to create and extend an unlimited + dataset. The program first writes integers to a dataset + with dataspace dimensions of DIM0xDIM1, then closes the + file. Next, it reopens the file, reads back the data, + outputs it to the screen, extends the dataset, and writes + new data to the extended portions of the dataset. Finally + it reopens the file again, reads back the data, and + outputs it to the screen. + + ************************************************************/ + +#include "hdf5.h" +#include <stdio.h> +#include <stdlib.h> + +#define FILE "h5ex_d_unlimadd.h5" +#define DATASET "DS1" +#define DIM0 4 +#define DIM1 7 +#define EDIM0 6 +#define EDIM1 10 +#define CHUNK0 4 +#define CHUNK1 4 + +int +main(void) +{ + hid_t file = H5I_INVALID_HID; + hid_t space = H5I_INVALID_HID; + hid_t dset = H5I_INVALID_HID; + hid_t dcpl = H5I_INVALID_HID; + herr_t status; + hsize_t dims[2] = {DIM0, DIM1}; + hsize_t extdims[2] = {EDIM0, EDIM1}; + hsize_t maxdims[2]; + hsize_t chunk[2] = {CHUNK0, CHUNK1}; + hsize_t start[2]; + hsize_t count[2]; + int wdata[DIM0][DIM1]; /* Write buffer */ + int wdata2[EDIM0][EDIM1]; /* Write buffer for extension */ + int **rdata = NULL; /* Read buffer */ + int ndims; + hsize_t i, j; + + /* + * Initialize data. + */ + for (i = 0; i < DIM0; i++) + for (j = 0; j < DIM1; j++) + wdata[i][j] = i * j - j; + + /* + * Create a new file using the default properties. + */ + file = H5Fcreate(FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT); + + /* + * Create dataspace with unlimited dimensions. + */ + maxdims[0] = H5S_UNLIMITED; + maxdims[1] = H5S_UNLIMITED; + space = H5Screate_simple(2, dims, maxdims); + + /* + * Create the dataset creation property list, and set the chunk + * size. + */ + dcpl = H5Pcreate(H5P_DATASET_CREATE); + status = H5Pset_chunk(dcpl, 2, chunk); + + /* + * Create the unlimited dataset. + */ + dset = H5Dcreate(file, DATASET, H5T_STD_I32LE, space, H5P_DEFAULT, dcpl, H5P_DEFAULT); + + /* + * Write the data to the dataset. + */ + status = H5Dwrite(dset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, wdata[0]); + + /* + * Close and release resources. + */ + status = H5Pclose(dcpl); + status = H5Dclose(dset); + status = H5Sclose(space); + status = H5Fclose(file); + + /* + * In this next section we read back the data, extend the dataset, + * and write new data to the extended portions. + */ + + /* + * Open file and dataset using the default properties. + */ + file = H5Fopen(FILE, H5F_ACC_RDWR, H5P_DEFAULT); + dset = H5Dopen(file, DATASET, H5P_DEFAULT); + + /* + * Get dataspace and allocate memory for read buffer. This is a + * two dimensional dataset so the dynamic allocation must be done + * in steps. + */ + space = H5Dget_space(dset); + ndims = H5Sget_simple_extent_dims(space, dims, NULL); + + /* + * Allocate array of pointers to rows. + */ + rdata = (int **)malloc(dims[0] * sizeof(int *)); + + /* + * Allocate space for integer data. + */ + rdata[0] = (int *)malloc(dims[0] * dims[1] * sizeof(int)); + + /* + * Set the rest of the pointers to rows to the correct addresses. + */ + for (i = 1; i < dims[0]; i++) + rdata[i] = rdata[0] + i * dims[1]; + + /* + * Read the data using the default properties. + */ + status = H5Dread(dset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, rdata[0]); + + /* + * Output the data to the screen. + */ + printf("Dataset before extension:\n"); + for (i = 0; i < dims[0]; i++) { + printf(" ["); + for (j = 0; j < dims[1]; j++) + printf(" %3d", rdata[i][j]); + printf("]\n"); + } + + status = H5Sclose(space); + + /* + * Extend the dataset. + */ + status = H5Dset_extent(dset, extdims); + + /* + * Retrieve the dataspace for the newly extended dataset. + */ + space = H5Dget_space(dset); + + /* + * Initialize data for writing to the extended dataset. + */ + for (i = 0; i < EDIM0; i++) + for (j = 0; j < EDIM1; j++) + wdata2[i][j] = j; + + /* + * Select the entire dataspace. + */ + status = H5Sselect_all(space); + + /* + * Subtract a hyperslab reflecting the original dimensions from the + * selection. The selection now contains only the newly extended + * portions of the dataset. + */ + start[0] = 0; + start[1] = 0; + count[0] = dims[0]; + count[1] = dims[1]; + status = H5Sselect_hyperslab(space, H5S_SELECT_NOTB, start, NULL, count, NULL); + + /* + * Write the data to the selected portion of the dataset. + */ + status = H5Dwrite(dset, H5T_NATIVE_INT, H5S_ALL, space, H5P_DEFAULT, wdata2[0]); + + /* + * Close and release resources. + */ + free(rdata[0]); + free(rdata); + status = H5Dclose(dset); + status = H5Sclose(space); + status = H5Fclose(file); + + /* + * Now we simply read back the data and output it to the screen. + */ + + /* + * Open file and dataset using the default properties. + */ + file = H5Fopen(FILE, H5F_ACC_RDONLY, H5P_DEFAULT); + dset = H5Dopen(file, DATASET, H5P_DEFAULT); + + /* + * Get dataspace and allocate memory for the read buffer as before. + */ + space = H5Dget_space(dset); + ndims = H5Sget_simple_extent_dims(space, dims, NULL); + rdata = (int **)malloc(dims[0] * sizeof(int *)); + rdata[0] = (int *)malloc(dims[0] * dims[1] * sizeof(int)); + for (i = 1; i < dims[0]; i++) + rdata[i] = rdata[0] + i * dims[1]; + + /* + * Read the data using the default properties. + */ + status = H5Dread(dset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, rdata[0]); + + /* + * Output the data to the screen. + */ + printf("\nDataset after extension:\n"); + for (i = 0; i < dims[0]; i++) { + printf(" ["); + for (j = 0; j < dims[1]; j++) + printf(" %3d", rdata[i][j]); + printf("]\n"); + } + + /* + * Close and release resources. + */ + free(rdata[0]); + free(rdata); + status = H5Dclose(dset); + status = H5Sclose(space); + status = H5Fclose(file); + + return 0; +} |