Source code for pm4py.visualization.decisiontree.variants.classic

'''
    PM4Py – A Process Mining Library for Python
Copyright (C) 2024 Process Intelligence Solutions UG (haftungsbeschränkt)

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as
published by the Free Software Foundation, either version 3 of the
License, or any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see this software project's root or
visit <https://www.gnu.org/licenses/>.

Website: https://processintelligence.solutions
Contact: info@processintelligence.solutions
'''
import tempfile
from pm4py.util import exec_utils, constants
from enum import Enum
from sklearn.tree import DecisionTreeClassifier
from sklearn.tree import export_graphviz
from typing import Optional, Dict, Any, Union, List
import graphviz




class Parameters(Enum):
    FORMAT = "format"
    ENABLE_GRAPH_TITLE = "enable_graph_title"
    GRAPH_TITLE = "graph_title"





def apply(
    clf: DecisionTreeClassifier,
    feature_names: List[str],
    classes: List[str],
    parameters: Optional[Dict[Union[str, Parameters], Any]] = None,
) -> graphviz.Source:
    """
    Apply the visualization of the decision tree

    Parameters
    ------------
    clf
        Decision tree
    feature_names
        Names of the provided features
    classes
        Names of the target classes
    parameters
        Possible parameters of the algorithm, including:
            Parameters.FORMAT -> Image format (pdf, svg, png ...)

    Returns
    ------------
    gviz
        GraphViz object
    """
    if parameters is None:
        parameters = {}

    enable_graph_title = exec_utils.get_param_value(
        Parameters.ENABLE_GRAPH_TITLE,
        parameters,
        constants.DEFAULT_ENABLE_GRAPH_TITLES,
    )
    graph_title = exec_utils.get_param_value(
        Parameters.GRAPH_TITLE, parameters, "Decision Tree"
    )

    format = exec_utils.get_param_value(Parameters.FORMAT, parameters, "png")
    filename = tempfile.NamedTemporaryFile(suffix=".gv")
    filename.close()

    dot_data = export_graphviz(
        clf,
        out_file=None,
        feature_names=feature_names,
        class_names=classes,
        filled=True,
        rounded=True,
        special_characters=True,
    )

    if enable_graph_title:
        dot_data = dot_data.replace(
            "digraph Tree {",
            f'digraph Tree {{\ngraph [label="{graph_title}", labelloc=t, fontsize=20];',
        )

    gviz = graphviz.Source(dot_data)
    gviz.format = format
    gviz.filename = filename.name

    return gviz