qiskit.transpiler.Layout.combine_into_edge_map¶

Layout.combine_into_edge_map(another_layout)[source]¶

Combines self and another_layout into an "edge map".

For example:

   self       another_layout  resulting edge map
qr_1 -> 0        0 <- q_2         qr_1 -> q_2
qr_2 -> 2        2 <- q_1         qr_2 -> q_1
qr_3 -> 3        3 <- q_0         qr_3 -> q_0

The edge map is used to compose dags via, for example, compose.

Parameters: another_layout (Layout) -- The other layout to combine.
Returns: A "edge map".
Return type: dict
Raises: LayoutError -- another_layout can be bigger than self, but not smaller. Otherwise, raises.