qiskit.visualization.dag_drawer

qiskit.visualization.dag_drawer(dag, scale=0.7, filename=None, style='color')

Plot the directed acyclic graph (dag) to represent operation dependencies in a quantum circuit.

This function calls the graphviz_draw() function from the rustworkx package to draw the DAG.

Parameters

• dag (DAGCircuit orDAGDependency) – The dag to draw.
• scale (float) – scaling factor
• filename (str) – file path to save image to (format inferred from name)
• style (str) – ‘plain’: B&W graph ‘color’ (default): color input/output/op nodes

Returns

if in Jupyter notebook and not saving to file,

otherwise None.

Return type

PIL.Image

Raises

• VisualizationError – when style is not recognized.
• InvalidFileError – when filename provided is not valid
• ValueError – If the file extension for filename is not an image type supported by Graphviz.

Example

from qiskit import QuantumRegister, ClassicalRegister, QuantumCircuit
from qiskit.dagcircuit import DAGCircuit
from qiskit.converters import circuit_to_dag
from qiskit.visualization import dag_drawer

q = QuantumRegister(3, 'q')
c = ClassicalRegister(3, 'c')
circ = QuantumCircuit(q, c)
circ.h(q[0])
circ.cx(q[0], q[1])
circ.measure(q[0], c[0])
with circ.if_test((c, 2)):
    circ.rz(0.5, q[1])

dag = circuit_to_dag(circ)
dag_drawer(dag)