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Diffstat (limited to 'HDF5Examples/JAVA/H5D/H5Ex_D_Sofloat.java')
-rw-r--r-- | HDF5Examples/JAVA/H5D/H5Ex_D_Sofloat.java | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/HDF5Examples/JAVA/H5D/H5Ex_D_Sofloat.java b/HDF5Examples/JAVA/H5D/H5Ex_D_Sofloat.java new file mode 100644 index 0000000..17f6e30 --- /dev/null +++ b/HDF5Examples/JAVA/H5D/H5Ex_D_Sofloat.java @@ -0,0 +1,361 @@ +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * + * Copyright by The HDF Group. * + * 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 COPYING file, which can be found at the root of the source code * + * distribution tree, or in https://www.hdfgroup.org/licenses. * + * If you do not have access to either file, you may request a copy from * + * help@hdfgroup.org. * + * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ + +/************************************************************ + This example shows how to read and write data to a dataset + using the Scale-Offset filter. The program first checks + if the Scale-Offset filter is available, then if it is it + writes floating point numbers to a dataset using + Scale-Offset, then closes the file Next, it reopens the + file, reads back the data, and outputs the type of filter + and the maximum value in the dataset to the screen. + ************************************************************/ + +import java.text.DecimalFormat; +import java.text.DecimalFormatSymbols; +import java.util.EnumSet; +import java.util.HashMap; +import java.util.Locale; +import java.util.Map; + +import hdf.hdf5lib.H5; +import hdf.hdf5lib.HDF5Constants; + +public class H5Ex_D_Sofloat { + + private static String FILENAME = "H5Ex_D_Sofloat.h5"; + private static String DATASETNAME = "DS1"; + private static final int DIM_X = 32; + private static final int DIM_Y = 64; + private static final int CHUNK_X = 4; + private static final int CHUNK_Y = 8; + private static final int RANK = 2; + private static final int NDIMS = 2; + + // Values for the status of space allocation + enum H5Z_filter { + H5Z_FILTER_ERROR(HDF5Constants.H5Z_FILTER_ERROR), + H5Z_FILTER_NONE(HDF5Constants.H5Z_FILTER_NONE), + H5Z_FILTER_DEFLATE(HDF5Constants.H5Z_FILTER_DEFLATE), + H5Z_FILTER_SHUFFLE(HDF5Constants.H5Z_FILTER_SHUFFLE), + H5Z_FILTER_FLETCHER32(HDF5Constants.H5Z_FILTER_FLETCHER32), + H5Z_FILTER_SZIP(HDF5Constants.H5Z_FILTER_SZIP), + H5Z_FILTER_NBIT(HDF5Constants.H5Z_FILTER_NBIT), + H5Z_FILTER_SCALEOFFSET(HDF5Constants.H5Z_FILTER_SCALEOFFSET), + H5Z_FILTER_RESERVED(HDF5Constants.H5Z_FILTER_RESERVED), + H5Z_FILTER_MAX(HDF5Constants.H5Z_FILTER_MAX); + private static final Map<Integer, H5Z_filter> lookup = new HashMap<Integer, H5Z_filter>(); + + static + { + for (H5Z_filter s : EnumSet.allOf(H5Z_filter.class)) + lookup.put(s.getCode(), s); + } + + private int code; + + H5Z_filter(int layout_type) { this.code = layout_type; } + + public int getCode() { return this.code; } + + public static H5Z_filter get(int code) { return lookup.get(code); } + } + + private static boolean checkScaleoffsetFilter() + { + try { + int available = H5.H5Zfilter_avail(HDF5Constants.H5Z_FILTER_SCALEOFFSET); + if (available == 0) { + System.out.println("Scale-Offset filter not available."); + return false; + } + } + catch (Exception e) { + e.printStackTrace(); + } + + try { + int filter_info = H5.H5Zget_filter_info(HDF5Constants.H5Z_FILTER_SCALEOFFSET); + if (((filter_info & HDF5Constants.H5Z_FILTER_CONFIG_ENCODE_ENABLED) == 0) || + ((filter_info & HDF5Constants.H5Z_FILTER_CONFIG_DECODE_ENABLED) == 0)) { + System.out.println("Scale-Offset filter not available for encoding and decoding."); + return false; + } + } + catch (Exception e) { + e.printStackTrace(); + } + return true; + } + + private static void writeData() + { + long file_id = HDF5Constants.H5I_INVALID_HID; + long filespace_id = HDF5Constants.H5I_INVALID_HID; + long dataset_id = HDF5Constants.H5I_INVALID_HID; + long dcpl_id = HDF5Constants.H5I_INVALID_HID; + long[] dims = {DIM_X, DIM_Y}; + long[] chunk_dims = {CHUNK_X, CHUNK_Y}; + double[][] dset_data = new double[DIM_X][DIM_Y]; + + // Initialize data. + for (int indx = 0; indx < DIM_X; indx++) + for (int jndx = 0; jndx < DIM_Y; jndx++) { + double x = indx; + double y = jndx; + dset_data[indx][jndx] = (x + 1) / (y + 0.3) + y; + } + + // Find the maximum value in the dataset, to verify that it was read correctly. + double max = dset_data[0][0]; + double min = dset_data[0][0]; + for (int indx = 0; indx < DIM_X; indx++) + for (int jndx = 0; jndx < DIM_Y; jndx++) { + if (max < dset_data[indx][jndx]) + max = dset_data[indx][jndx]; + if (min > dset_data[indx][jndx]) + min = dset_data[indx][jndx]; + } + + // Print the maximum value. + DecimalFormat df = new DecimalFormat("#,##0.000000", new DecimalFormatSymbols(Locale.US)); + System.out.println("Maximum value in write buffer is: " + df.format(max)); + System.out.println("Minimum value in write buffer is: " + df.format(min)); + + // Create a new file using the default properties. + try { + file_id = H5.H5Fcreate(FILENAME, HDF5Constants.H5F_ACC_TRUNC, HDF5Constants.H5P_DEFAULT, + HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Create dataspace. Setting maximum size to NULL sets the maximum size to be the current size. + try { + filespace_id = H5.H5Screate_simple(RANK, dims, null); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Create the dataset creation property list, add the Scale-Offset + // filter and set the chunk size. + try { + dcpl_id = H5.H5Pcreate(HDF5Constants.H5P_DATASET_CREATE); + if (dcpl_id >= 0) { + H5.H5Pset_scaleoffset(dcpl_id, HDF5Constants.H5Z_SO_FLOAT_DSCALE, 2); + H5.H5Pset_chunk(dcpl_id, NDIMS, chunk_dims); + } + } + catch (Exception e) { + e.printStackTrace(); + } + + // Create the dataset. + try { + if ((file_id >= 0) && (filespace_id >= 0) && (dcpl_id >= 0)) + dataset_id = H5.H5Dcreate(file_id, DATASETNAME, HDF5Constants.H5T_IEEE_F64LE, filespace_id, + HDF5Constants.H5P_DEFAULT, dcpl_id, HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Write the data to the dataset. + try { + if (dataset_id >= 0) + H5.H5Dwrite(dataset_id, HDF5Constants.H5T_NATIVE_DOUBLE, HDF5Constants.H5S_ALL, + HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, dset_data); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Close and release resources. + try { + if (dcpl_id >= 0) + H5.H5Pclose(dcpl_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + try { + if (dataset_id >= 0) + H5.H5Dclose(dataset_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + try { + if (filespace_id >= 0) + H5.H5Sclose(filespace_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Close file + try { + if (file_id >= 0) + H5.H5Fclose(file_id); + } + catch (Exception e) { + e.printStackTrace(); + } + } + + private static void readData() + { + long file_id = HDF5Constants.H5I_INVALID_HID; + long dataset_id = HDF5Constants.H5I_INVALID_HID; + long dcpl_id = HDF5Constants.H5I_INVALID_HID; + double[][] dset_data = new double[DIM_X][DIM_Y]; + + // Open file using the default properties. + try { + file_id = H5.H5Fopen(FILENAME, HDF5Constants.H5F_ACC_RDONLY, HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + // Open dataset using the default properties. + try { + if (file_id >= 0) + dataset_id = H5.H5Dopen(file_id, DATASETNAME, HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Retrieve dataset creation property list. + try { + if (dataset_id >= 0) + dcpl_id = H5.H5Dget_create_plist(dataset_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Retrieve and print the filter type. Here we only retrieve the + // first filter because we know that we only added one filter. + try { + if (dcpl_id >= 0) { + // Java lib requires a valid filter_name object and cd_values + int[] flags = {0}; + long[] cd_nelmts = {1}; + int[] cd_values = {0}; + String[] filter_name = {""}; + int[] filter_config = {0}; + int filter_type = -1; + + filter_type = H5.H5Pget_filter(dcpl_id, 0, flags, cd_nelmts, cd_values, 120, filter_name, + filter_config); + System.out.print("Filter type is: "); + switch (H5Z_filter.get(filter_type)) { + case H5Z_FILTER_DEFLATE: + System.out.println("H5Z_FILTER_DEFLATE"); + break; + case H5Z_FILTER_SHUFFLE: + System.out.println("H5Z_FILTER_SHUFFLE"); + break; + case H5Z_FILTER_FLETCHER32: + System.out.println("H5Z_FILTER_FLETCHER32"); + break; + case H5Z_FILTER_SZIP: + System.out.println("H5Z_FILTER_SZIP"); + break; + case H5Z_FILTER_NBIT: + System.out.println("H5Z_FILTER_NBIT"); + break; + case H5Z_FILTER_SCALEOFFSET: + System.out.println("H5Z_FILTER_SCALEOFFSET"); + break; + default: + System.out.println("H5Z_FILTER_ERROR"); + } + System.out.println(); + } + } + catch (Exception e) { + e.printStackTrace(); + } + + // Read the data using the default properties. + try { + if (dataset_id >= 0) + H5.H5Dread(dataset_id, HDF5Constants.H5T_NATIVE_DOUBLE, HDF5Constants.H5S_ALL, + HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, dset_data); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Find the maximum value in the dataset, to verify that it was read correctly. + double max = dset_data[0][0]; + double min = dset_data[0][0]; + for (int indx = 0; indx < DIM_X; indx++) + for (int jndx = 0; jndx < DIM_Y; jndx++) { + if (max < dset_data[indx][jndx]) + max = dset_data[indx][jndx]; + if (min > dset_data[indx][jndx]) + min = dset_data[indx][jndx]; + } + + // Print the maximum value. + DecimalFormat df = new DecimalFormat("#,##0.000000", new DecimalFormatSymbols(Locale.US)); + System.out.println("Maximum value in " + DATASETNAME + " is: " + df.format(max)); + System.out.println("Minimum value in " + DATASETNAME + " is: " + df.format(min)); + + // End access to the dataset and release resources used by it. + try { + if (dcpl_id >= 0) + H5.H5Pclose(dcpl_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + try { + if (dataset_id >= 0) + H5.H5Dclose(dataset_id); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Close the file. + try { + if (file_id >= 0) + H5.H5Fclose(file_id); + } + catch (Exception e) { + e.printStackTrace(); + } + } + + public static void main(String[] args) + { + + // Check if Scale-Offset compression is available and can be used + // for both compression and decompression. 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. + if (H5Ex_D_Sofloat.checkScaleoffsetFilter()) { + H5Ex_D_Sofloat.writeData(); + H5Ex_D_Sofloat.readData(); + } + } +} |