--- a +++ b/Stats/_LogisticRegression.py @@ -0,0 +1,93 @@ +#!/usr/bin/env python +# -*- coding: UTF-8 -*- +# +# Copyright 2017 University of Westminster. All Rights Reserved. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# ============================================================================== +""" It is an interface for the 'LogisticRegression' training model (Logistic Regression). +""" + +from typing import Dict, List, Any, TypeVar +from Stats.Stats import Stats +from sklearn import linear_model + +PandasDataFrame = TypeVar('DataFrame') +SklearnLogisticRegression = TypeVar('LogisticRegression') + +__author__ = "Mohsen Mesgarpour" +__copyright__ = "Copyright 2016, https://github.com/mesgarpour" +__credits__ = ["Mohsen Mesgarpour"] +__license__ = "GPL" +__version__ = "1.1" +__maintainer__ = "Mohsen Mesgarpour" +__email__ = "mohsen.mesgarpour@gmail.com" +__status__ = "Release" + + +class _LogisticRegression(Stats): + def __init__(self): + """Initialise the objects and constants. + """ + super(self.__class__, self).__init__() + self._logger.debug(__name__) + self._logger.debug("Run Logistic Regression.") + + def train(self, + features_indep_df: PandasDataFrame, + feature_target: List, + model_labals: List=[0, 1], + **kwargs: Any) -> SklearnLogisticRegression: + """Perform the training, using the Logistic Regression. + :param features_indep_df: the independent features, which are inputted into the model. + :param feature_target: the target feature, which is being estimated. + :param model_labals: the target labels (default [0, 1]). + :param kwargs: penalty='l2', dual=False, tol=0.0001, C=1.0, fit_intercept=True, intercept_scaling=1, + class_weight=None, random_state=None, solver='liblinear', max_iter=100, multi_class='ovr', + verbose=0, warm_start=False, n_jobs=-1 + :return: the trained model. + """ + self._logger.debug("Train " + __name__) + model_train = linear_model.LogisticRegression(**kwargs) + model_train.fit(features_indep_df.values, feature_target) + return model_train + + def train_summaries(self, + model_train: SklearnLogisticRegression) -> Dict: + """Produce the training summary. + :param model_train: the instance of the trained model. + :return: the training summary. + """ + self._logger.debug("Summarise " + __name__) + summaries = dict() + # Coefficient of the features in the decision function. + summaries["coef_"] = model_train.coef_ + # Intercept (a.k.a. bias) added to the decision function. + summaries["intercept_"] = model_train.intercept_ + # Actual number of iterations for all classes. If binary or multinomial, it returns only 1 element. + summaries["n_iter_"] = model_train.n_iter_ + return summaries + + def plot(self, + model_train: SklearnLogisticRegression, + feature_names: List, + class_names: List=["True", "False"]): + """Plot the tree diagram. + :param model_train: the instance of the trained model. + :param feature_names: the names of input features. + :param class_names: the predicted class labels. + :return: the model graph. + """ + self._logger.debug("Plot " + __name__) + # todo: plot + pass