h5
What is a .h5 file?
application/x-hdf5
HDF5 (.h5) is a binary container format for large, heterogeneous scientific data. It stores multidimensional arrays (datasets) in a hierarchical group structure with attributes and chunked, compressed storage, and is standard in ML, physics, and geoscience.
How to use a .h5 file
Use an example .h5 file to test HDF5 readers (h5py, PyTables), group and dataset traversal, and attribute extraction.
Download example .h5 files
- HDF5 — Hierarchical Scientific DataA small HDF5 file with a compound 'employees' dataset and a numeric 'readings' grid — the hierarchical format used across science and ML. For testing h5py/HDF5 readers and conversion.
- HDF5 Experiment Hierarchy — raw, processed, metadata (.h5)A three-group HDF5 file laid out the way a real bench run is — raw arrays, a processed derivative that names its source in a derived_from attribute, and a metadata group — with units on every dataset. It is the walk-the-tree fixture: a reader has to recurse rather than assume a flat namespace.
- HDF5 Chunked + gzip + shuffle Filters (.h5)One array stored twice in the same file: chunked with the shuffle and gzip filters applied, and contiguous with no filters at all. Comparing the two proves a reader ran the HDF5 filter pipeline rather than reading raw chunk bytes.
- HDF5 Compound Record dtype — Mixed Field Types (.h5)A compound-dtype dataset mixing an integer key, two float measurements, a fixed-width byte string and a boolean flag in a single record. It is the fixture for readers that must map an HDF5 record type onto a native struct without reordering or repadding the fields.
- HDF5 Strings — Fixed, Variable-Length and UTF-8 (.h5)Fixed-width byte strings, variable-length UTF-8 strings and UTF-8 attribute text in one file, including Greek, CJK and combining diacritics. HDF5 hands fixed-width strings back as padded bytes and variable-length ones as decoded text, and conflating the two is where string handling usually breaks.
- HDF5 Units and Uncertainty Attributes on Every Dataset (.h5)Four measured quantities where the uncertainty lives in dataset attributes rather than a parallel column, with the coverage factor spelled out so k=1 and k=2 values cannot be confused. It is the fixture for a pipeline that must propagate uncertainty it read from metadata.
- HDF5 Dimension Scales Attached to a 3-D Array (.h5)The CF NetCDF grid expressed with HDF5's own dimension-scale mechanism, so each axis of the 3-D array points at a real coordinate dataset through DIMENSION_LIST references. It lets a reader be tested on scale resolution instead of on filename conventions.
- MATLAB v7.3 (.mat) Variable Store — the HDF5 File It Actually Is (.h5)A MATLAB v7.3 variable store, which is an HDF5 file with a 512-byte MATLAB user block and MATLAB_class attributes — the bytes are the same whichever extension you give it. Because MATLAB is column-major, A appears in HDF5 as its own transpose, which is the conversion bug this fixture is built around.
and 6 more in the library.