标签:就是 grid fit knn算法 测试 最优 numpy 执行 select
主要用到 sklearn.model_selection包下的GridSearchCV类。
总共分为几步:
a.创建训练集和测试集
b.创建最优参数字典
c.构建GridSearchCV对象
d.进行数据训练
e.得出最优超参数
a.创建训练集和测试集
import numpy as np from sklearn.neighbors import KNeighborsClassifier from sklearn import datasets from sklearn.model_selection import train_test_split from sklearn.model_selection import GridSearchCV digits = datasets.load_digits() x = digits.data y = digits.target x_train,x_test,y_train,y_test = train_test_split(x,y,test_size=0.2,random_state=666)
b.创建最优参数字典
param_digits =[ { ‘weights‘:[‘uniform‘], ‘n_neighbors‘:[i for i in range(1,11)] }, { ‘weights‘:[‘distance‘], ‘n_neighbors‘:[i for i in range(1,6)], ‘p‘:[i for i in range(1,6)] } ]
c.构建GridSearchCV对象
knn_grid = KNeighborsClassifier() grid_search = GridSearchCV(knn_grid,param_digits,n_jobs=-1,verbose=2)#n_job指的是所用的核数,也就是多线程执行,当等于-1时,也就是等于你的计算机的核数,verbose越大,打印的信息越详细
d.进行数据训练
grid_search.fit(x_train,y_train)
e.得出最优超参数
param = grid_search.best_params_ print(param)
标签:就是 grid fit knn算法 测试 最优 numpy 执行 select
原文地址:https://www.cnblogs.com/lyr999736/p/10665572.html