determine_backend_multi(dispatchables, *, domain, only=True, coerce=False, **kwargs)

This is useful for functions that call multimethods without any dispatchable arguments. You can use determine_backend_multi to ensure the same backend is used everywhere in a block of multimethod calls involving multiple arrays.

Notes

Support is determined by the __ua_convert__ protocol. Backends not supporting the type must return NotImplemented from their __ua_convert__ if they don't support input of that type.

Parameters

dispatchables: Sequence[Union[uarray.Dispatchable, Any]] :

The dispatchables that must be supported

domain: string :

The domain to query for backends and set.

coerce: bool :

Whether or not to allow coercion to the backend's types. Implies only .

only: bool :

Whether or not this should be the last backend to try.

dispatch_type: Optional[Any] :

The default dispatch type associated with dispatchables , aka " marking <MarkingGlossary> ".

Set a backend supporting all dispatchables

See Also

determine_backend

For a single dispatch value

set_backend

For when you know which backend to set

Examples

determine_backend allows the backend to be set from a single object. determine_backend_multi allows multiple objects to be checked simultaneously for support in the backend. Suppose we have a BackendAB which supports TypeA and TypeB in the same call, and a BackendBC that doesn't support TypeA .

This example is valid syntax, but we were not able to check execution

>>> with ua.set_backend(ex.BackendAB), ua.set_backend(ex.BackendBC):
...     a, b = ex.TypeA(), ex.TypeB()
...     with ua.determine_backend_multi(
...         [ua.Dispatchable(a, "mark"), ua.Dispatchable(b, "mark")],
...         domain="ua_examples"
...     ):
...         res = ex.creation_multimethod()
...         ex.call_multimethod(res, a, b)
TypeA

This won't call BackendBC because it doesn't support TypeA .

We can also use leave out the ua.Dispatchable if we specify the default dispatch_type for the dispatchables argument.

This example is valid syntax, but we were not able to check execution

>>> with ua.set_backend(ex.BackendAB), ua.set_backend(ex.BackendBC):
...     a, b = ex.TypeA(), ex.TypeB()
...     with ua.determine_backend_multi(
...         [a, b], dispatch_type="mark", domain="ua_examples"
...     ):
...         res = ex.creation_multimethod()
...         ex.call_multimethod(res, a, b)
TypeA

See :

Back References

The following pages refer to to this document either explicitly or contain code examples using this.

scipy._lib._uarray._backend.determine_backend_multi

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GitHub : /scipy/_lib/_uarray/_backend.py#617
type: <class 'function'>
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