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Diffstat (limited to 'HDF5Examples/JAVA/H5D/H5Ex_D_Transform.java')
| -rw-r--r-- | HDF5Examples/JAVA/H5D/H5Ex_D_Transform.java | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/HDF5Examples/JAVA/H5D/H5Ex_D_Transform.java b/HDF5Examples/JAVA/H5D/H5Ex_D_Transform.java new file mode 100644 index 0000000..9ad7e79 --- /dev/null +++ b/HDF5Examples/JAVA/H5D/H5Ex_D_Transform.java @@ -0,0 +1,249 @@ +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * + * 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 a data transform expression. The program first + writes integers to a dataset using the transform + expression TRANSFORM, then closes the file. Next, it + reopens the file, reads back the data without a transform, + and outputs the data to the screen. Finally it reads the + data using the transform expression RTRANSFORM and outputs + the results to the screen. + ************************************************************/ + +import hdf.hdf5lib.H5; +import hdf.hdf5lib.HDF5Constants; + +public class H5Ex_D_Transform { + + private static String FILE = "H5Ex_D_Transform.h5"; + private static String DATASET = "DS1"; + private static final int DIM_X = 4; + private static final int DIM_Y = 7; + private static String TRANSFORM = "x+1"; + private static String RTRANSFORM = "x-1"; + + 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 dxpl_id = HDF5Constants.H5I_INVALID_HID; + + long[] dims = {DIM_X, DIM_Y}; + int[][] dset_data = new int[DIM_X][DIM_Y]; + + // Initialize data. + for (int i = 0; i < DIM_X; i++) + for (int j = 0; j < DIM_Y; j++) + dset_data[i][j] = i * j - j; + + // Output the data to the screen. + System.out.println("Original Data:"); + for (int i = 0; i < DIM_X; i++) { + System.out.print(" ["); + for (int j = 0; j < DIM_Y; j++) + System.out.print(" " + dset_data[i][j] + " "); + System.out.println("]"); + } + + // Create a new file using the default properties. + try { + file_id = H5.H5Fcreate(FILE, 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(2, dims, null); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Create the dataset transfer property list and define the transform expression. + try { + dxpl_id = H5.H5Pcreate(HDF5Constants.H5P_DATASET_XFER); + if (dxpl_id >= 0) + H5.H5Pset_data_transform(dxpl_id, TRANSFORM); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Create the dataset using the default properties. Unfortunately we must save as + // a native type or the transform operation will fail. + try { + if ((file_id >= 0) && (filespace_id >= 0)) + dataset_id = H5.H5Dcreate(file_id, DATASET, HDF5Constants.H5T_NATIVE_INT, filespace_id, + HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, + HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Write the data to the dataset using the dataset transfer property list. + try { + if ((dataset_id >= 0) && (dxpl_id >= 0)) + H5.H5Dwrite(dataset_id, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL, + HDF5Constants.H5S_ALL, dxpl_id, dset_data); + } + catch (Exception e) { + e.printStackTrace(); + } + + // End access to the dataset and release resources used by it. + try { + if (dxpl_id >= 0) + H5.H5Pclose(dxpl_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 the 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 dxpl_id = HDF5Constants.H5I_INVALID_HID; + int[][] dset_data = new int[DIM_X][DIM_Y]; + + // Open an existing file using the default properties. + try { + file_id = H5.H5Fopen(FILE, HDF5Constants.H5F_ACC_RDONLY, HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Open an existing dataset using the default properties. + try { + if (file_id >= 0) + dataset_id = H5.H5Dopen(file_id, DATASET, HDF5Constants.H5P_DEFAULT); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Read the data using the default properties. + try { + if (dataset_id >= 0) + H5.H5Dread(dataset_id, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL, + HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, dset_data); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Output the data to the screen. + System.out.println("Data as written with transform '" + TRANSFORM + "'"); + for (int i = 0; i < DIM_X; i++) { + System.out.print(" ["); + for (int j = 0; j < DIM_Y; j++) + System.out.print(" " + dset_data[i][j] + " "); + System.out.println("]"); + } + + // Create the dataset transfer property list and define the transform expression. + try { + dxpl_id = H5.H5Pcreate(HDF5Constants.H5P_DATASET_XFER); + if (dxpl_id >= 0) + H5.H5Pset_data_transform(dxpl_id, RTRANSFORM); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Read the data using the dataset transfer property list. + try { + if ((dataset_id >= 0) && (dxpl_id >= 0)) + H5.H5Dread(dataset_id, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL, + HDF5Constants.H5S_ALL, dxpl_id, dset_data); + } + catch (Exception e) { + e.printStackTrace(); + } + + // Output the data to the screen. + + System.out.println("Data as written with transform '" + TRANSFORM + "' and read with transform '" + + RTRANSFORM + "'"); + for (int i = 0; i < DIM_X; i++) { + System.out.print(" ["); + for (int j = 0; j < DIM_Y; j++) + System.out.print(" " + dset_data[i][j] + " "); + System.out.println("]"); + } + + // Close and release resources. + try { + if (dxpl_id >= 0) + H5.H5Pclose(dxpl_id); + } + catch (Exception e) { + e.printStackTrace(); + } + try { + if (dataset_id >= 0) + H5.H5Dclose(dataset_id); + } + catch (Exception e) { + e.printStackTrace(); + } + try { + if (file_id >= 0) + H5.H5Fclose(file_id); + } + catch (Exception e) { + e.printStackTrace(); + } + } + + public static void main(String[] args) + { + H5Ex_D_Transform.writeData(); + H5Ex_D_Transform.readData(); + } +} |