# Copyright (C) 2023 qBraid
#
# This file is part of the qBraid-SDK
#
# The qBraid-SDK is free software released under the GNU General Public License v3
# or later. You can redistribute and/or modify it under the terms of the GPL v3.
# See the LICENSE file in the project root or <https://www.gnu.org/licenses/gpl-3.0.html>.
#
# THERE IS NO WARRANTY for the qBraid-SDK, as per Section 15 of the GPL v3.
"""
Module for plotting qBraid transpiler quantum program conversion graphs.
"""
from typing import TYPE_CHECKING, Dict, Optional
import matplotlib.pyplot as plt
import networkx as nx
from qbraid.programs._import import QPROGRAM_LIBS
if TYPE_CHECKING:
import qbraid.transpiler
[docs]
def plot_conversion_graph( # pylint: disable=too-many-arguments
graph: "qbraid.transpiler.ConversionGraph",
title: Optional[str] = "qBraid Quantum Program Conversion Graph",
legend: bool = False,
seed: Optional[int] = None,
node_size: int = 1200,
min_target_margin: int = 18,
show: bool = True,
save_path: Optional[str] = None,
colors: Optional[Dict[str, str]] = None,
) -> None:
"""
Plot the conversion graph using matplotlib. The graph is displayed using node
and edge color conventions, with options for a title, legend, and figure saving.
Args:
graph (qbraid.interface.ConversionGraph): The directed conversion graph to be plotted.
title (Optional[str]): Title of the plot. Defaults to
'qBraid Quantum Program Conversion Graph'.
legend (bool): If True, display a legend on the graph. Defaults to False.
seed (Optional[int]): Seed for the node layout algorithm. Useful for consistent positioning.
Defaults to None.
node_size (int): Size of the nodes. Defaults to 1200.
min_target_margin (int): Minimum target margin for edges. Defaults to 18.
show (bool): If True, display the figure. Defaults to True.
save_path (Optional[str]): Path to save the figure. If None, the figure is not saved.
Defaults to None.
colors (Optional[Dict[str, str]]): Dictionary for node and edge colors. Expected keys are
'qbraid_node', 'external_node', 'qbraid_edge', 'external_edge'. Defaults to None.
Returns:
None
"""
# Set default colors if not provided
if colors is None:
colors = {
"qbraid_node": "lightblue",
"external_node": "lightgray",
"qbraid_edge": "gray",
"external_edge": "blue",
"extras_edge": "red",
}
# Extract colors and apply them in the drawing
ncolors = [
colors["qbraid_node"] if node in QPROGRAM_LIBS else colors["external_node"]
for node in graph.nodes()
]
# Create a dictionary for quick lookup of conversions by their source and target
conversion_dict = {
(conversion.source, conversion.target): conversion for conversion in graph.conversions()
}
conversions_ordered = [
conversion_dict[(edge[0], edge[1])]
for edge in graph.edges()
if (edge[0], edge[1]) in conversion_dict
]
ecolors = [
(
colors["qbraid_edge"]
if graph[edge.source][edge.target]["native"]
else colors["external_edge"] if edge.supported else colors["extras_edge"]
)
for edge in conversions_ordered
]
pos = nx.spring_layout(graph, seed=seed) # good seeds: 123, 134
nx.draw_networkx_nodes(graph, pos, node_color=ncolors, node_size=node_size)
nx.draw_networkx_edges(graph, pos, edge_color=ecolors, min_target_margin=min_target_margin)
nx.draw_networkx_labels(graph, pos)
if title:
plt.title(title)
plt.axis("off")
if legend:
# Create legend elements using a loop
legend_info = [
("qBraid - Node", "o", colors["qbraid_node"], None),
("External - Node", "o", colors["external_node"], None),
("qBraid - Edge", None, colors["qbraid_edge"], "-"),
("Extras - Edge", None, colors["extras_edge"], "-"),
("External - Edge", None, colors["external_edge"], "-"),
]
legend_elements = [
plt.Line2D(
[0],
[0],
marker=marker,
color="w" if marker else color,
label=label,
markersize=10 if marker else None,
markerfacecolor=color if marker else None,
linestyle=linestyle,
linewidth=2 if linestyle else None,
)
for label, marker, color, linestyle in legend_info
]
plt.legend(handles=legend_elements, loc="best")
if show:
plt.show()
if save_path:
plt.savefig(save_path)