HDF (.hdf)

  • Import and Export support the scientific dataset (SD) data model of the HDF format.
  • Background

      MIME type: application/x-hdf
      HDF data format Version 4.
      General-purpose format for representing multidimensional datasets.
      Used for storage, management, and exchange of scientific data.
      HDF is an acronym for Hierarchical Data Format.
      Developed by the US National Center for Supercomputing Applications (NCSA).
      Binary file format.
      Incompatible with HDF Version 5.

    Import and Export

    • Import["file.hdf"] imports an HDF file, returning the names of the datasets stored in the file.
    • Export["file.hdf",expr] exports a multidimensional array to an HDF file.
    • Import["file.hdf"] returns a list of strings representing the names of all datasets contained in the file.
    • Export["file.hdf",{expr1,},{"Datasets",{"/dataset1",}}] creates an HDF file, storing the arrays {expr1,} as separate datasets.
    • Import["file.hdf",elem] imports the specified element from an HDF file.
    • Import["file.hdf",{elem,suba,subb,}] imports a subelement.
    • Import["file.hdf",{{elem1,elem2,}}] imports multiple elements.
    • The import format can be specified with Import["file","HDF"] or Import["file",{"HDF",elem,}].
    • Export["file.hdf",expr,elem] creates an HDF file by treating expr as specifying element elem.
    • Export["file.hdf",{expr1,expr2,},{{elem1,elem2,}}] treats each expri as specifying the corresponding elemi.
    • Export["file.hdf",expr,opt1->val1,] exports expr with the specified option elements taken to have the specified values.
    • Export["file.hdf",{elem1->expr1,elem2->expr2,},"Rules"] uses rules to specify the elements to be exported.
    • See the reference pages for full general information on Import and Export.
    • ImportString and ExportString support the HDF format.


    • General Import elements:
    • "Elements"list of elements and options available in this file
      "Rules"full list of rules for each element and option
      "Options"list of rules for options, properties, and settings
    • Data representation elements:
    • "Data"all datasets imported as a list of arrays
      "Datasets"names of all datasets
    • Import by default uses the "Datasets" element for the HDF format.
    • Specifying and selecting datasets:
    • "Datasets",nn^(th) dataset
      "Datasets",datasetnamed dataset
    • Meta-information elements:
    • "DataFormat"type used to represent each dataset
      "Dimensions"data dimensions of each dataset
    • The following values can be given for "DataFormat":
    • "Integer8"8-bit integers
      "Integer16"16-bit integers
      "Integer32"32-bit integers
      "UnsignedInteger8"8-bit unsigned integers
      "UnsignedInteger16"16-bit unsigned integers
      "UnsignedInteger32"32-bit unsigned integers
      "Real32"IEEE single-precision numbers
      "Real64"IEEE double-precision numbers


    • Export option:
    • "Append"Falsewhether to append to an existing file


    Basic Examples  (2)

    Show the names of datasets in a file:

    Click for copyable input

    Import a dataset and render it as a raster image:

    Click for copyable input
    Click for copyable input

    Render as ArrayPlot, specifying a color scheme:

    Click for copyable input

    Rasterize the color image and export the data to HDF:

    Click for copyable input

    Create a random matrix and export it to HDF:

    Click for copyable input
    Click for copyable input

    Show the datasets contained in the generated file:

    Click for copyable input

    Import the data:

    Click for copyable input

    See Also


    Introduced in 2004
    | Updated in 2007