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Matrix representation of circuit

See original GitHub issue

What is the expected enhancement?

It would be great to be able to inspect the unitary matrix of a circuit that can be represented as such. Currently one can go through Operator to get a representation but it’s not obvious to a user how to do this. A circuit.to_matrix method or similar would make this much clearer and easily accessible. However, not all circuits have a matrix representation and thus this would not be universal.

Issue Analytics

State:
Created 4 years ago
Reactions:2
Comments:7 (7 by maintainers)

Top GitHub Comments

1reaction

chriseclecticcommented, Sep 20, 2019

I don’t think this should be a circuit method:

It hides the fact you are doing an expensive simulation to determine the matrix
Many circuits won’t have a matrix representation
For many circuits the the matrix will typically be too large for available memory (around >14 or so qubits)

It would be better to better document to the user how to use the Operator class or unitary simulator to do this

0reactions

1ucian0commented, Sep 19, 2021

closing this issues as wont fix. Please, reopen if there are new arguments for a QuantumCircuit.to_matrix method.