class opt_einsum.paths.PathOptimizer[source]

Base class for different path optimizers to inherit from.

Subclassed optimizers should define a call method with signature:

def __call__(self, inputs, output, size_dict, memory_limit=None):
    inputs : list[set[str]]
        The indices of each input array.
    outputs : set[str]
        The output indices
    size_dict : dict[str, int]
        The size of each index
    memory_limit : int, optional
        If given, the maximum allowed memory.
    # ... compute path here ...
    return path

where path is a list of int-tuples specifiying a contraction order.


Initialize self. See help(type(self)) for accurate signature.


__call__(inputs, output, size_dict[, …])

Call self as a function.

__delattr__(name, /)

Implement delattr(self, name).


Default dir() implementation.

__eq__(value, /)

Return self==value.

__format__(format_spec, /)

Default object formatter.

__ge__(value, /)

Return self>=value.

__getattribute__(name, /)

Return getattr(self, name).

__gt__(value, /)

Return self>value.


Return hash(self).


Initialize self.


This method is called when a class is subclassed.

__le__(value, /)

Return self<=value.

__lt__(value, /)

Return self<value.

__ne__(value, /)

Return self!=value.


Create and return a new object.


Helper for pickle.

__reduce_ex__(protocol, /)

Helper for pickle.


Return repr(self).

__setattr__(name, value, /)

Implement setattr(self, name, value).


Size of object in memory, in bytes.


Return str(self).


Abstract classes can override this to customize issubclass().

_check_args_against_first_call(inputs, …)

Utility that stateful optimizers can use to ensure they are not called with different contractions across separate runs.






list of weak references to the object (if defined)