h5disp

Display contents of HDF5 file

Syntax

h5disp(filename)

h5disp(filename,loc)

h5disp(filename,loc,mode)

h5disp(___,'TextEncoding','UTF-8')

Description

h5disp(filename) displays the metadata that describes the structure of the specified HDF5 file.

h5disp(filename,loc) displays the metadata for the specified location within the file.

h5disp(filename,loc,mode), where mode is 'min', displays only the group and dataset names. The default for mode is 'simple', which displays the dataset metadata and attribute values.

h5disp(___,'TextEncoding','UTF-8') forces object and attribute names to be treated as UTF-8-encoded text. This usage is unnecessary if the HDF5 file accurately specifies the use of UTF-8 encoding.

Examples

Metadata of HDF5 File

Create a 50-by-50 dataset with a chunk size of 5-by-5.

h5create('exampleFile2.h5','/exampleDataset',[50,50],'ChunkSize',[5 5])

Display the metadata of the HDF5 file. In this example, the HDF5 file contains one dataset within its root group. The attributes belonging to the dataset are displayed below its name.

h5disp('exampleFile2.h5')

HDF5 exampleFile2.h5 
Group '/' 
    Dataset 'exampleDataset' 
        Size:  50x50
        MaxSize:  50x50
        Datatype:   H5T_IEEE_F64LE (double)
        ChunkSize:  5x5
        Filters:  none
        FillValue:  0.000000

Attributes of Dataset in HDF5 File

Display the attributes of a dataset /g4/world in the file example.h5. If you specify the full path of a dataset in an HDF5 file, h5disp will only display the attributes of the dataset.

h5disp('example.h5','/g4/world')

HDF5 example.h5 
Dataset 'world' 
    Size:  36x19
    MaxSize:  36x19
    Datatype:   H5T_IEEE_F64LE (double)
    ChunkSize:  []
    Filters:  none
    FillValue:  0.000000

Display Mode

Display only group and dataset names by specifying the display mode 'min'.

h5disp('example.h5','/g4/world','min')

HDF5 example.h5 
Dataset 'world' 

Input Arguments

filename — Filename

string scalar | character vector

Filename of an existing HDF5 file, specified as a string scalar or character vector.

Depending on the location of your file, filename can take one of these forms.

Location	Form
Current folder	Specify the name of the file in filename. Example: "myFile.h5"
Other folders	If the file is not in the current folder or in a folder on the MATLAB® path, then specify the full or relative path in filename. Example: "C:\myFolder\myFile.h5" Example: "myFolder\myFile.h5"
Uniform resource locator (URL) (since R2024b)	If the file is located by an internet URL, then filename must contain the protocol type, such as http://. For more information, see Work with Remote Data. Example: "http://my_hostname/my_path/my_file.h5"
Remote location	If the file is stored at a remote location, then filename must contain the full path of the file specified as a uniform resource locator (URL) of the form: scheme_name://path_to_file/filename Based on your remote location, scheme_name can be one of the values in this table. Remote Location scheme_name Amazon S3™ s3 Windows Azure® Blob Storage wasb, wasbs HDFS™ hdfs For more information, see Work with Remote Data. Example: "s3://myBucket/myFolder/myFile.h5"

• If your file consists of several physical files using the Family driver, specify filename using a format specifier. For example, to use the Family driver with the two files family0.h5 and family1.h5, specify filename as "family%d.h5".

• If your file consists of several physical files using the Multi driver or the Split driver, specify filename as the leading prefix of the names of the physical files. For example, to use the Multi driver with the six files multi-b.h5, multi-g.h5, multi-l.h5, multi-o.h5, multi-r.h5, and multi-s.h5, specify filename as "multi".

loc — Location in file

character vector | string scalar

Location in the file, specified as a character vector or string scalar containing the full path to a location in the file. To display the metadata for the entire file, specify '/' as the location. If loc is a group, h5disp displays all objects in the group.

mode — Display mode

'simple' (default) | 'min'

Display mode, specified as one of these values:

• 'simple' — Display dataset names and attribute values if the attribute is an integer, floating point, or a scalar string.

• 'min' — Display only group and dataset names.

Limitations

• MATLAB does not support internet URLs that require authentication.

• MATLAB Online™ supports internet URLs associated with Microsoft^® OneDrive™ files and folders, while the installed version of MATLAB supports only local OneDrive files.

• The h5disp function output omits information for datasets and attributes that fail file integrity checks. (since R2024b)

Version History

Introduced in R2011a

R2024b: Datasets and attributes that fail file integrity checks no longer supported (R2024b Update)

The h5disp function issues a warning for datasets and attributes that fail file integrity checks and omits information about those datasets and attributes from its output. Previously, this function did not issue a warning for such datasets or attributes and included information about those datasets and attributes in its output. The warning takes this form:

Warning: Unable to read 'datasetName' from the file. A portion of the file may be corrupt.

R2024b: Display metadata of HDF5 files over HTTP and HTTPS

You can display metadata of HDF5 files stored in primary online sources by using the h5disp function with an internet URL.

R2020b: Display metadata of HDF5 files stored remotely

You can display metadata of HDF5 files stored in remote locations, such as Amazon S3, Windows Azure Blob Storage, and HDFS.

R2020b: Display metadata of HDF5 files with Unicode names

You can display metadata of HDF5 files whose names are encoded as Unicode characters.