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python sklearn常用分类算法模型的调用

更新时间:2020-08-03 16:36:01 作者:startmvc
本文实例为大家分享了pythonsklearn分类算法模型调用的具体代码,供大家参考,具体内容如

本文实例为大家分享了python sklearn分类算法模型调用的具体代码,供大家参考,具体内容如下

实现对'NB', 'KNN', 'LR', 'RF', 'DT', 'SVM','SVMCV', 'GBDT'模型的简单调用。


# coding=gbk
 
import time 
from sklearn import metrics 
import pickle as pickle 
import pandas as pd
 
 
# Multinomial Naive Bayes Classifier 
def naive_bayes_classifier(train_x, train_y): 
 from sklearn.naive_bayes import MultinomialNB 
 model = MultinomialNB(alpha=0.01) 
 model.fit(train_x, train_y) 
 return model 
 
 
# KNN Classifier 
def knn_classifier(train_x, train_y): 
 from sklearn.neighbors import KNeighborsClassifier 
 model = KNeighborsClassifier() 
 model.fit(train_x, train_y) 
 return model 
 
 
# Logistic Regression Classifier 
def logistic_regression_classifier(train_x, train_y): 
 from sklearn.linear_model import LogisticRegression 
 model = LogisticRegression(penalty='l2') 
 model.fit(train_x, train_y) 
 return model 
 
 
# Random Forest Classifier 
def random_forest_classifier(train_x, train_y): 
 from sklearn.ensemble import RandomForestClassifier 
 model = RandomForestClassifier(n_estimators=8) 
 model.fit(train_x, train_y) 
 return model 
 
 
# Decision Tree Classifier 
def decision_tree_classifier(train_x, train_y): 
 from sklearn import tree 
 model = tree.DecisionTreeClassifier() 
 model.fit(train_x, train_y) 
 return model 
 
 
# GBDT(Gradient Boosting Decision Tree) Classifier 
def gradient_boosting_classifier(train_x, train_y): 
 from sklearn.ensemble import GradientBoostingClassifier 
 model = GradientBoostingClassifier(n_estimators=200) 
 model.fit(train_x, train_y) 
 return model 
 
 
# SVM Classifier 
def svm_classifier(train_x, train_y): 
 from sklearn.svm import SVC 
 model = SVC(kernel='rbf', probability=True) 
 model.fit(train_x, train_y) 
 return model 
 
# SVM Classifier using cross validation 
def svm_cross_validation(train_x, train_y): 
 from sklearn.grid_search import GridSearchCV 
 from sklearn.svm import SVC 
 model = SVC(kernel='rbf', probability=True) 
 param_grid = {'C': [1e-3, 1e-2, 1e-1, 1, 10, 100, 1000], 'gamma': [0.001, 0.0001]} 
 grid_search = GridSearchCV(model, param_grid, n_jobs = 1, verbose=1) 
 grid_search.fit(train_x, train_y) 
 best_parameters = grid_search.best_estimator_.get_params() 
 for para, val in list(best_parameters.items()): 
 print(para, val) 
 model = SVC(kernel='rbf', C=best_parameters['C'], gamma=best_parameters['gamma'], probability=True) 
 model.fit(train_x, train_y) 
 return model 
 
def read_data(data_file): 
 data = pd.read_csv(data_file)
 train = data[:int(len(data)*0.9)]
 test = data[int(len(data)*0.9):]
 train_y = train.label
 train_x = train.drop('label', axis=1)
 test_y = test.label
 test_x = test.drop('label', axis=1)
 return train_x, train_y, test_x, test_y
 
if __name__ == '__main__': 
 data_file = "H:\\Research\\data\\trainCG.csv" 
 thresh = 0.5 
 model_save_file = None 
 model_save = {} 
 
 test_classifiers = ['NB', 'KNN', 'LR', 'RF', 'DT', 'SVM','SVMCV', 'GBDT'] 
 classifiers = {'NB':naive_bayes_classifier, 
 'KNN':knn_classifier, 
 'LR':logistic_regression_classifier, 
 'RF':random_forest_classifier, 
 'DT':decision_tree_classifier, 
 'SVM':svm_classifier, 
 'SVMCV':svm_cross_validation, 
 'GBDT':gradient_boosting_classifier 
 } 
 
 print('reading training and testing data...') 
 train_x, train_y, test_x, test_y = read_data(data_file) 
 
 for classifier in test_classifiers: 
 print('******************* %s ********************' % classifier) 
 start_time = time.time() 
 model = classifiers[classifier](train_x, train_y) 
 print('training took %fs!' % (time.time() - start_time)) 
 predict = model.predict(test_x) 
 if model_save_file != None: 
 model_save[classifier] = model 
 precision = metrics.precision_score(test_y, predict) 
 recall = metrics.recall_score(test_y, predict) 
 print('precision: %.2f%%, recall: %.2f%%' % (100 * precision, 100 * recall)) 
 accuracy = metrics.accuracy_score(test_y, predict) 
 print('accuracy: %.2f%%' % (100 * accuracy)) 
 
 if model_save_file != None: 
 pickle.dump(model_save, open(model_save_file, 'wb')) 

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。

python sklearn分类算法模型调用 python分类算法模型调用 python sklearn分类算法