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Diffstat (limited to 'HDF5Examples/FORTRAN/H5D/h5ex_d_checksum.F90')
| -rw-r--r-- | HDF5Examples/FORTRAN/H5D/h5ex_d_checksum.F90 | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/HDF5Examples/FORTRAN/H5D/h5ex_d_checksum.F90 b/HDF5Examples/FORTRAN/H5D/h5ex_d_checksum.F90 new file mode 100644 index 0000000..b0464a3 --- /dev/null +++ b/HDF5Examples/FORTRAN/H5D/h5ex_d_checksum.F90 @@ -0,0 +1,166 @@ +! ************************************************************ +! +! This example shows how to read and write data to a dataset +! using the Fletcher32 checksum filter. The program first +! checks if the Fletcher32 filter is available, then if it +! is it writes integers to a dataset using Fletcher32, then +! closes the file. Next, it reopens the file, reads back +! the data, checks if the filter detected an error and +! outputs the type of filter and the maximum value in the +! dataset to the screen. +! +! This file is intended for use with HDF5 Library version 1.8 +! +! ************************************************************* +PROGRAM main + + USE HDF5 + + IMPLICIT NONE + + CHARACTER(LEN=18), PARAMETER :: filename = "h5ex_d_checksum.h5" + CHARACTER(LEN=3) , PARAMETER :: dataset = "DS1" + INTEGER , PARAMETER :: dim0 = 32 + INTEGER , PARAMETER :: dim1 = 64 + INTEGER , PARAMETER :: chunk0 = 4 + INTEGER , PARAMETER :: chunk1 = 8 + + INTEGER(HID_T) :: file, space, dset, dcpl ! Handles + INTEGER :: hdferr + LOGICAL :: avail + INTEGER(HSIZE_T), DIMENSION(1:2) :: dims = (/dim0, dim1/), chunk =(/chunk0,chunk1/) + INTEGER(SIZE_T) :: nelmts + INTEGER, DIMENSION(1:1) :: cd_values + INTEGER :: flags, filter_info + INTEGER, DIMENSION(1:dim0, 1:dim1) :: wdata, & ! Write buffer + rdata ! Read buffer + INTEGER :: filter_id + INTEGER :: filter_info_both + INTEGER :: max, i, j + INTEGER(SIZE_T), PARAMETER :: MaxChrLen = 80 + CHARACTER(LEN=MaxChrLen) :: name + ! + ! Initialize FORTRAN interface. + ! + CALL h5open_f(hdferr) + ! + ! Check if the Fletcher32 filter is available and can be used for + ! both encoding and decoding. Normally we do not perform error + ! checking in these examples for the sake of clarity, but in this + ! case we will make an exception because this filter is an + ! optional part of the hdf5 library. + ! + CALL h5zfilter_avail_f(H5Z_FILTER_FLETCHER32_F, avail, hdferr) + + IF (.NOT.avail) THEN + WRITE(*,'("N-Bit filter not available.",/)') + STOP + ENDIF + + CALL h5zget_filter_info_f(H5Z_FILTER_FLETCHER32_F, filter_info, hdferr) + + filter_info_both=IOR(H5Z_FILTER_ENCODE_ENABLED_F,H5Z_FILTER_DECODE_ENABLED_F) + IF (filter_info .NE. filter_info_both) THEN + WRITE(*,'("N-Bit filter not available for encoding and decoding.",/)') + STOP + ENDIF + ! + ! Initialize data. + ! + DO i = 1, dim0 + DO j = 1, dim1 + wdata(i,j) = i * j - j + ENDDO + ENDDO + ! + ! Create a new file using the default properties. + ! + CALL h5fcreate_f(filename, H5F_ACC_TRUNC_F, file, hdferr) + ! + ! Create dataspace. Setting size to be the current size. + ! + CALL h5screate_simple_f(2, dims, space, hdferr) + ! + ! Create the dataset creation property list, add the N-Bit filter + ! and set the chunk size. + ! + CALL h5pcreate_f(H5P_DATASET_CREATE_F, dcpl, hdferr) + CALL h5pset_fletcher32_f(dcpl, hdferr) + CALL h5pset_chunk_f(dcpl, 2, chunk, hdferr) + ! + ! Create the dataset. + ! + CALL h5dcreate_f(file, dataset, H5T_STD_I32LE, space, dset, hdferr, dcpl) + ! + ! Write the data to the dataset. + ! + CALL h5dwrite_f(dset, H5T_NATIVE_INTEGER, wdata, dims, hdferr) + ! + ! Close and release resources. + ! + CALL h5pclose_f(dcpl , hdferr) + CALL h5dclose_f(dset , hdferr) + CALL h5sclose_f(space, hdferr) + CALL h5fclose_f(file , hdferr) + ! + ! Now we begin the read section of this example. + ! + ! + ! Open file and dataset using the default properties. + ! + CALL h5fopen_f(filename, H5F_ACC_RDONLY_F, file, hdferr) + CALL h5dopen_f (file, dataset, dset, hdferr) + ! + ! Retrieve dataset creation property list. + ! + CALL h5dget_create_plist_f(dset, dcpl, hdferr) + ! + ! Retrieve and print the filter type. Here we only retrieve the + ! first filter because we know that we only added one filter. + ! + nelmts = 0 + CALL H5Pget_filter_f(dcpl, 0, flags, nelmts, cd_values, MaxChrLen, name, filter_id, hdferr) + WRITE(*,'("Filter type is: ")', ADVANCE='NO') + IF(filter_id.EQ.H5Z_FILTER_DEFLATE_F)THEN + WRITE(*,'(T2,"H5Z_FILTER_DEFLATE_F")') + ELSE IF(filter_id.EQ.H5Z_FILTER_SHUFFLE_F)THEN + WRITE(*,'(T2,"H5Z_FILTER_SHUFFLE_F")') + ELSE IF(filter_id.EQ.H5Z_FILTER_FLETCHER32_F)THEN + WRITE(*,'(T2,"H5Z_FILTER_FLETCHER32_F")') + ELSE IF(filter_id.EQ.H5Z_FILTER_SZIP_F)THEN + WRITE(*,'(T2,"H5Z_FILTER_SZIP_F")') + ENDIF + ! + ! Read the data using the default properties. + ! + CALL h5dread_f(dset, H5T_NATIVE_INTEGER, rdata, dims, hdferr) + ! + ! Check if the read was successful. Normally we do not perform + ! error checking in these examples for the sake of clarity, but in + ! this case we will make an exception because this is how the + ! fletcher32 checksum filter reports data errors. + ! + IF (hdferr.LT.0)THEN + WRITE(*,'("Dataset read failed!")') + CALL h5pclose_f(dcpl , hdferr) + CALL h5dclose_f(dset , hdferr) + CALL h5fclose_f(file , hdferr) + STOP + ENDIF + ! + ! Find the maximum value in the dataset, to verify that it was + ! read correctly. + ! + max = MAXVAL(rdata) + ! + ! Print the maximum value. + ! + WRITE(*,'("Maximum value in ",A," is: ",i10)') dataset, max + ! + ! Close and release resources. + ! + CALL h5pclose_f(dcpl , hdferr) + CALL h5dclose_f(dset , hdferr) + CALL h5fclose_f(file , hdferr) + +END PROGRAM main |