/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 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 files COPYING and Copyright.html. COPYING can be found at the root * * of the source code distribution tree; Copyright.html can be found at the * * root level of an installed copy of the electronic HDF5 document set and * * is linked from the top-level documents page. It can also be found at * * http://hdfgroup.org/HDF5/doc/Copyright.html. If you do not have * * access to either file, you may request a copy from help@hdfgroup.org. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* * This example demonstrates the use of NBIT filter for compound datatype * 1. Prepare the datatype for the dataset * 2. Define the creation property list for the dataset * 3. Set the use of NBIT filter in the creation property list * 4. Write to and read data from the dataset, then compare the data * 5. Clean up * See description of H5Pset_nbit() in the HDF5 Reference Manual. */ #include "hdf5.h" #include #include #define H5FILE_NAME "nbit_compound.h5" #define DATASET_NAME "nbit_compound" #define NX 200 #define NY 300 #define CH_NX 10 #define CH_NY 15 int main(void) { typedef struct { /* Struct with atomic fields */ int i; char c; short s; float f; } atomic; hid_t file, i_tid, c_tid, s_tid, f_tid; hid_t cmpd_tid; /* atomic compound datatype */ hid_t mem_cmpd_tid; /* memory atomic compound datatype */ size_t precision[3] = {15, 7, 10}; size_t offset[3] = {9, 0, 3}; hid_t dataset, space, dc; const hsize_t size[2] = {2, 5}; const hsize_t chunk_size[2] = {2, 5}; const float float_val[2][5] = {{(float)188384.00, (float)19.103516, (float)-1.0831790e9, (float)-84.242188, (float)5.2045898}, {(float)-49140.000, (float)2350.2500, (float)-3.2110596e-1, (float)6.4998865e-5, (float)-0.0000000}}; atomic orig_data[2][5]; atomic new_data[2][5]; unsigned int i_mask, s_mask, c_mask; size_t i, j; /* Define datatypes for members of the compound type */ i_tid = H5Tcopy(H5T_NATIVE_INT); c_tid = H5Tcopy(H5T_NATIVE_CHAR); s_tid = H5Tcopy(H5T_NATIVE_SHORT); f_tid = H5Tcopy(H5T_IEEE_F32BE); /* Set precision and offset for the 1st member: int i */ if(H5Tset_precision(i_tid,precision[0]) < 0) goto error; if(H5Tset_offset(i_tid,offset[0]) < 0) goto error; /* Set precision and offset for the 2nd member: char c */ if(H5Tset_precision(c_tid,precision[1]) < 0) goto error; if(H5Tset_offset(c_tid,offset[1]) < 0) goto error; /* Set precision and offset for the 3rd member: short s */ if(H5Tset_precision(s_tid,precision[2]) < 0) goto error; if(H5Tset_offset(s_tid,offset[2]) < 0) goto error; /* Set fields, offset, precision, size and ebias for the 4th member: float f */ if(H5Tset_fields(f_tid, (size_t)26, (size_t)20, (size_t)6, (size_t)7, (size_t)13) < 0) goto error; if(H5Tset_offset(f_tid, (size_t)7) < 0) goto error; if(H5Tset_precision(f_tid, (size_t)20) < 0) goto error; if(H5Tset_size(f_tid, (size_t)4) < 0) goto error; if(H5Tset_ebias(f_tid, (size_t)31) < 0) goto error; /* Create a memory compound datatype before setting the order */ mem_cmpd_tid = H5Tcreate(H5T_COMPOUND, sizeof(atomic)); if(H5Tinsert(mem_cmpd_tid, "i", HOFFSET(atomic, i), i_tid) < 0) goto error; if(H5Tinsert(mem_cmpd_tid, "c", HOFFSET(atomic, c), c_tid) < 0) goto error; if(H5Tinsert(mem_cmpd_tid, "s", HOFFSET(atomic, s), s_tid) < 0) goto error; if(H5Tinsert(mem_cmpd_tid, "f", HOFFSET(atomic, f), H5T_NATIVE_FLOAT) < 0) goto error; /* Set order of dataset compound member datatype */ if(H5Tset_order(i_tid, H5T_ORDER_BE) < 0) goto error; if(H5Tset_order(c_tid, H5T_ORDER_BE) < 0) goto error; if(H5Tset_order(s_tid, H5T_ORDER_BE) < 0) goto error; /* Create a dataset compound datatype and insert some atomic types */ cmpd_tid = H5Tcreate(H5T_COMPOUND, sizeof(atomic)); if(H5Tinsert(cmpd_tid, "i", HOFFSET(atomic, i), i_tid) < 0) goto error; if(H5Tinsert(cmpd_tid, "c", HOFFSET(atomic, c), c_tid) < 0) goto error; if(H5Tinsert(cmpd_tid, "s", HOFFSET(atomic, s), s_tid) < 0) goto error; if(H5Tinsert(cmpd_tid, "f", HOFFSET(atomic, f), f_tid) < 0) goto error; /* Create the data space */ if((space = H5Screate_simple(2, size, NULL)) < 0) goto error; /* * Set chunk and nbit filter. * Note that application using the NBIT filter must store data with chunked storage. */ if((dc = H5Pcreate(H5P_DATASET_CREATE)) < 0) goto error; if(H5Pset_chunk(dc, 2, chunk_size) < 0) goto error; if(H5Pset_nbit(dc) < 0) goto error; /* Create the HDF5 file */ if((file = H5Fcreate (H5FILE_NAME, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0) { printf("Error: fail to create file\n"); goto error; } /* Create the dataset */ if((dataset = H5Dcreate2(file, DATASET_NAME, cmpd_tid, space, H5P_DEFAULT, dc, H5P_DEFAULT)) < 0) goto error; /* Initialize data, assuming size of long_long >= size of member datatypes */ for(i= 0;i< (size_t)size[0]; i++) for(j = 0; j < (size_t)size[1]; j++) { orig_data[i][j].i = (int)(((long_long)random() % (long_long)pow(2.0, (double)(precision[0]-1))) << offset[0]); orig_data[i][j].c = (char)(((long_long)random() % (long_long)pow(2.0, (double)(precision[1]-1))) << offset[1]); orig_data[i][j].s = (short)(((long_long)random() % (long_long)pow(2.0, (double)(precision[2]-1))) << offset[2]); orig_data[i][j].f = float_val[i][j]; /* some even-numbered integer values are negtive */ if((i*size[1]+j+1)%2 == 0) { orig_data[i][j].i = -orig_data[i][j].i; orig_data[i][j].s = -orig_data[i][j].s; } } /* Write the data to the dataset and then close it */ if(H5Dwrite(dataset, mem_cmpd_tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, orig_data) < 0) goto error; H5Dclose(dataset); /* Reopen the dataset */ if ((dataset = H5Dopen2(file, DATASET_NAME, H5P_DEFAULT)) < 0) { printf("Error: fail to open dataset\n"); goto error; } /* Read the data back from the dataset to a buffer */ if(H5Dread(dataset, mem_cmpd_tid, H5S_ALL, H5S_ALL, H5P_DEFAULT, new_data) < 0) goto error; /* * Check that the values read are the same as the values written * Use mask for checking the significant bits, ignoring the padding bits * Exit and return error on the first different value encountered. */ i_mask = ~(~0 << (precision[0] + offset[0])) & (~0 << offset[0]); c_mask = ~(~0 << (precision[1] + offset[1])) & (~0 << offset[1]); s_mask = ~(~0 << (precision[2] + offset[2])) & (~0 << offset[2]); for(i = 0; i < size[0]; i++) { for(j = 0; j < size[1]; j++) { if((new_data[i][j].i & i_mask) != (orig_data[i][j].i & i_mask) || (new_data[i][j].c & c_mask) != (orig_data[i][j].c & c_mask) || (new_data[i][j].s & s_mask) != (orig_data[i][j].s & s_mask) || (orig_data[i][j].f==orig_data[i][j].f && new_data[i][j].f != orig_data[i][j].f)) { printf("Read different values than written.\n"); goto error; } } } /* * Cleanup */ if(H5Tclose(i_tid) < 0) goto error; if(H5Tclose(c_tid) < 0) goto error; if(H5Tclose(s_tid) < 0) goto error; if(H5Tclose(f_tid) < 0) goto error; if(H5Tclose(cmpd_tid) < 0) goto error; if(H5Tclose(mem_cmpd_tid) < 0) goto error; if(H5Pclose(dc) < 0) goto error; if(H5Sclose(space) < 0) goto error; if(H5Dclose(dataset) < 0) goto error; return 0; error: return -1; }