How to save mpl image to file

[camillerievan]

Hi,

Nice library. Is there a way to save the mpl image to a file, rather than display it on screen?

Thanks

Evan

[Hiroya-W]

Hi @camillerievan

If you are running from the command line (not on Jupyter Notebook), you can use the following program.

from qulacs import QuantumCircuit
import matplotlib.pyplot as plt
from qulacsvis.visualization import MPLCircuitlDrawer # Use instead of circuit_drawer

# Build a your quantum circuit
circuit = QuantumCircuit(3)
circuit.add_X_gate(0)
circuit.add_Y_gate(1)
circuit.add_Z_gate(2)
circuit.add_dense_matrix_gate(
    [0, 1], [[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 0, 1], [0, 0, 1, 0]]
)
circuit.add_CNOT_gate(2, 0)
circuit.add_X_gate(2)

drawer = MPLCircuitlDrawer(circuit)
fig = drawer.draw()
plt.savefig("output.png") # save to file

However, in many cases you will want to run it on Jupyter Notebook. This is apparently broken. Sorry. I am working on fixing this.

[camillerievan]

Thanks - works great!

[Hiroya-W]

• ✨ Support for saving images to file #110

Fixed. Upgrade qulacsvis to v0.7.0 and use it this way.

circuit_drawer(circuit, "mpl", filename="output.png")