grids.core.GenericGrid.from_hdf5#

classmethod GenericGrid.from_hdf5(filename: str, group_name: str | None = None, **kwargs)[source]#

Load a grid instance from an HDF5 file.

This method reconstructs a fully initialized grid object from a file written by to_hdf5(). It restores all structural metadata, coordinate arrays, unit definitions, and the associated coordinate system.

Parameters:

filename (str) – Path to the HDF5 file to load from.
group_name (str, optional) – Name of the HDF5 group in which the grid was saved. If None, loads from the file root.
**kwargs – Additional keyword arguments forwarded to the grid constructor.

Returns:

Reconstructed grid instance.

Return type:

GenericGrid

Notes

The structure of the input HDF5 file will look something like the following:

├── [attrs]
│   ├── axes                → list of str           # Axis names (e.g. ["x", "y", "z"])
│   ├── chunking            → bool                  # Whether chunking is enabled
│   ├── chunk_size          → list[int]             # Size of each chunk (if enabled)
│   ├── grid_shape          → list[int]             # Grid shape (excluding ghost zones)
│   ├── bbox                → (2, ndim) array       # Physical bounding box
│   ├── ghost_zones         → (2, ndim) array       # Ghost zones on each axis
│   └── coordinate_system   → str                   # Class name of the coordinate system
│
│
├── coordinates/            → group                 # Note: names vary with coordinate system.
│   ├── x                   → 1D array              # Coordinate values along 'x' axis
│   ├── y                   → 1D array              # Coordinate values along 'y' axis
│   └── z                   → 1D array              # Coordinate values along 'z' axis (if 3D)
│
├── units/                  → group
│   ├── length              → str (e.g. "cm")       # Unit string for 'length'
│   ├── time                → str (e.g. "s")        # Unit string for 'time'
│   ├── mass                → str (e.g. "g")        # Unit string for 'mass'
│   ├── angle               → str (e.g. "rad")      # Unit string for 'angle'
│   └── ...                                        # Any other base dimensions
│
└── coord_systm/            → group
    └── ...                 → Defined by coordinate system class
                             (symbolic metric, Jacobians, etc.)

grids.core.GenericGrid.from_hdf5#

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