import dascore as dc
spool = dc.get_example_spool("random_das").chunk(time=None)
patch = spool.get_lazy_patch()
# Only the sources needed for this selection are loaded.
sub = patch.select(time=(0, 1), relative=True)get_lazy_patch
get_lazy_patch(
self ,
index: int = 0,
)-> ‘PatchType’
Return the patch at index without loading its data.
The patch’s data loads, one source patch at a time, only when it is sliced (e.g. by Patch.select). This lets a long patch, such as one made by spool.chunk(time=None), be processed in pieces without holding it all in memory. The sources must continue one evenly sampled grid, so the patch’s coordinates match spool[index]; attributes come from the first source patch.
Parameters
| Parameter | Description |
|---|---|
| index | The index of the patch in the spool. |
Raises
ParameterError If the patch merges sources which don’t continue one evenly sampled grid, or which have coordinates along the merged dimension. CoordMergeError When a source is loaded whose dtype, samples, or other coordinates differ from what the first source implies.