Method hlg

dask/_expr.py:1363–1384

(self)

    @property
    def hlg(self):
        expr = self.operand("dsk")
        layers = expr.dsk.layers.copy()
        deps = expr.dsk.dependencies.copy()
        keys = expr.__dask_keys__()
        if isinstance(expr.postcompute, list):
            postcomputes = expr.postcompute
        else:
            postcomputes = [expr.postcompute]
        tasks = [
            Task(self._name, func, _convert_dask_keys(keys), *extra_args)
            for func, extra_args in postcomputes
        ]
        from dask.highlevelgraph import HighLevelGraph, MaterializedLayer

        leafs = set(deps)
        for val in deps.values():
            leafs -= val
        for t in tasks:
            layers[t.key] = MaterializedLayer({t.key: t})
            deps[t.key] = leafs
        return HighLevelGraph(layers, dependencies=deps)

    def __dask_keys__(self):
        return [self._name]