java读写.hdf5多数据集的例子

以下是一个使用Java读写.hdf5多数据集的例子：

import ncsa.hdf.hdf5lib.H5;
import ncsa.hdf.hdf5lib.HDF5Constants;

public class MultipleDatasetExample {

    public static void main(String[] args) {
        // Create a new HDF5 file
        int fileId = H5.H5Fcreate("example.h5", HDF5Constants.H5F_ACC_TRUNC, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);

        // Create two datasets and write data to them
        int dataset1Id = createDataset(fileId, "dataset1", new int[] { 2, 3 }, new int[] { 1, 2, 3, 4, 5, 6 });
        int dataset2Id = createDataset(fileId, "dataset2", new int[] { 3, 2 }, new double[] { 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 });

        // Read data from the datasets
        int[] data1 = readIntArrayDataset(dataset1Id);
        double[] data2 = readDoubleArrayDataset(dataset2Id);

        // Print the data
        System.out.println("Dataset 1:");
        for (int i = 0; i < data1.length; i++) {
            System.out.print(data1[i] + " ");
        }
        System.out.println();
        
        System.out.println("Dataset 2:");
        for (int i = 0; i < data2.length; i++) {
            System.out.print(data2[i] + " ");
        }
        System.out.println();

        // Close the datasets
        H5.H5Dclose(dataset1Id);
        H5.H5Dclose(dataset2Id);

        // Close the HDF5 file
        H5.H5Fclose(fileId);
    }

    private static int createDataset(int fileId, String name, int[] dimensions, int[] data) {
        // Create a new dataspace
        int dataspaceId = H5.H5Screate_simple(dimensions.length, dimensions, null);

        // Create a new dataset
        int datasetId = H5.H5Dcreate(fileId, "/" + name, HDF5Constants.H5T_STD_I32BE, dataspaceId, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);

        // Write the data to the dataset
        H5.H5Dwrite(datasetId, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL, HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, data);

        // Close the dataspace
        H5.H5Sclose(dataspaceId);

        return datasetId;
    }

    private static int createDataset(int fileId, String name, int[] dimensions, double[] data) {
        // Create a new dataspace
        int dataspaceId = H5.H5Screate_simple(dimensions.length, dimensions, null);

        // Create a new dataset
        int datasetId = H5.H5Dcreate(fileId, "/" + name, HDF5Constants.H5T_IEEE_F64BE, dataspaceId, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT, HDF5Constants.H5P_DEFAULT);

        // Write the data to the dataset
        H5.H5Dwrite(datasetId, HDF5Constants.H5T_NATIVE_DOUBLE, HDF5Constants.H5S_ALL, HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, data);

        // Close the dataspace
        H5.H5Sclose(dataspaceId);

        return datasetId;
    }

    private static int[] readIntArrayDataset(int datasetId) {
        // Get the dataspace and dimensions of the dataset
        int dataspaceId = H5.H5Dget_space(datasetId);
        int[] dimensions = new int[H5.H5Sget_simple_extent_ndims(dataspaceId)];
        H5.H5Sget_simple_extent_dims(dataspaceId, dimensions, null);

        // Read the data from the dataset
        int[] data = new int[dimensions[0] * dimensions[1]];
        H5.H5Dread(datasetId, HDF5Constants.H5T_NATIVE_INT, HDF5Constants.H5S_ALL, HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, data);

        // Close the dataspace
        H5.H5Sclose(dataspaceId);

        return data;
    }

    private static double[] readDoubleArrayDataset(int datasetId) {
        // Get the dataspace and dimensions of the dataset
        int dataspaceId = H5.H5Dget_space(datasetId);
        int[] dimensions = new int[H5.H5Sget_simple_extent_ndims(dataspaceId)];
        H5.H5Sget_simple_extent_dims(dataspaceId, dimensions, null);

        // Read the data from the dataset
        double[] data = new double[dimensions[0] * dimensions[1]];
        H5.H5Dread(datasetId, HDF5Constants.H5T_NATIVE_DOUBLE, HDF5Constants.H5S_ALL, HDF5Constants.H5S_ALL, HDF5Constants.H5P_DEFAULT, data);

        // Close the dataspace
        H5.H5Sclose(dataspaceId);

        return data;
    }
}

这个例子创建了一个新的.hdf5文件，然后创建了两个数据集，并将数据写入这些数据集。随后，它从这些数据集中读取数据，并将其打印到控制台上。最后，它关闭了这些数据集和.hdf5文件。