---
title: Decompose (v0.46)
description: API reference for qiskit.transpiler.passes.Decompose in qiskit v0.46
source: https://eu-de.quantum.cloud.ibm.com/docs/en/api/qiskit/0.46/qiskit.transpiler.passes.Decompose
---

# Decompose

*class* `qiskit.transpiler.passes.Decompose(*args, **kwargs)`

[GitHub](https://github.com/qiskit/qiskit/tree/stable/0.46/qiskit/transpiler/passes/basis/decompose.py)

Bases: [`TransformationPass`](/docs/api/qiskit/0.46/qiskit.transpiler.TransformationPass "qiskit.transpiler.basepasses.TransformationPass")

Expand a gate in a circuit using its decomposition rules.

Decompose initializer.

**Parameters**

**gates\_to\_decompose** – optional subset of gates to be decomposed, identified by gate label, name or type. Defaults to all gates.

## Attributes

### is\_analysis\_pass

Check if the pass is an analysis pass.

If the pass is an AnalysisPass, that means that the pass can analyze the DAG and write the results of that analysis in the property set. Modifications on the DAG are not allowed by this kind of pass.

### is\_transformation\_pass

Check if the pass is a transformation pass.

If the pass is a TransformationPass, that means that the pass can manipulate the DAG, but cannot modify the property set (but it can be read).

## Methods

### execute

`execute(passmanager_ir, state, callback=None)`

Execute optimization task for input Qiskit IR.

**Parameters**

- **passmanager\_ir** ([*Any*](https://docs.python.org/3/library/typing.html#typing.Any)) – Qiskit IR to optimize.
- **state** ([*PassManagerState*](/docs/api/qiskit/0.46/qiskit.passmanager.PassManagerState "qiskit.passmanager.compilation_status.PassManagerState")) – State associated with workflow execution by the pass manager itself.
- **callback** ([*Callable*](https://docs.python.org/3/library/collections.abc.html#collections.abc.Callable) *| None*) – A callback function which is caller per execution of optimization task.

**Returns**

Optimized Qiskit IR and state of the workflow.

**Return type**

[tuple](https://docs.python.org/3/library/stdtypes.html#tuple)\[[*Any*](https://docs.python.org/3/library/typing.html#typing.Any), [qiskit.passmanager.compilation\_status.PassManagerState](/docs/api/qiskit/0.46/qiskit.passmanager.PassManagerState "qiskit.passmanager.compilation_status.PassManagerState")]

### name

`name()`

Name of the pass.

**Return type**

[str](https://docs.python.org/3/library/stdtypes.html#str)

### run

`run(dag)`

Run the Decompose pass on dag.

**Parameters**

**dag** ([*DAGCircuit*](/docs/api/qiskit/0.46/qiskit.dagcircuit.DAGCircuit "qiskit.dagcircuit.dagcircuit.DAGCircuit")) – input dag.

**Returns**

output dag where `gate` was expanded.

**Return type**

[*DAGCircuit*](/docs/api/qiskit/0.46/qiskit.dagcircuit.DAGCircuit "qiskit.dagcircuit.dagcircuit.DAGCircuit")

### update\_status

`update_status(state, run_state)`

Update workflow status.

**Parameters**

- **state** ([*PassManagerState*](/docs/api/qiskit/0.46/qiskit.passmanager.PassManagerState "qiskit.passmanager.compilation_status.PassManagerState")) – Pass manager state to update.
- **run\_state** (*RunState*) – Completion status of current task.

**Returns**

Updated pass manager state.

**Return type**

[*PassManagerState*](/docs/api/qiskit/0.46/qiskit.passmanager.PassManagerState "qiskit.passmanager.compilation_status.PassManagerState")