下面给出代码进行测试: importnumpyasnpimporttimedeflinear_fit(x,y):z=np.polyfit(x,y,deg=1)returnzdefmylf(x,y):xa,ya=np.mean(x),np.mean(y)xs,ys=np.sum(x),np.sum(y)a=(3*np.dot(x,y)-xs*ys)/(3*np.dot(x,x)-xs*xs)b=ya-a*xareturnnp.array([a,b])x=[-1,1,1]y=...
linear.fit(x_train,y_train) coef['linear']=linear.coef_ #岭回归 Lambdas=np.logspace(-5,2,200) ridge_cv=RidgeCV(alphas=Lambdas,normalize=True,scoring='neg_mean_squared_error',cv=10) ridge_cv.fit(x_train,y_train) ridge_best_lambda=ridge_cv.alpha_ ridge=Ridge(alpha=ridge_best_lambda,...
五.封装与测试 接下来简单封装线性回归模型,并放到ml_models.linear_model模块便于后续使用; class LinearRegression(object): def __init__(self, fit_intercept=True, solver='sgd', if_standard=True, epochs=10, eta=1e-2, batch_size=1): """ :param fit_intercept: 是否训练bias :param solver: :...
import numpy as np class LinearRegression:def __init__(self, learning_rate=0.01, iterations=1000):self.learning_rate = learning_rate self.iterations = iterations self.weights = None self.bias = None def fit(self, x, y, num_features=None):num_samples, num_features = x.shape self.weigh...
from sklearn.linear_model import LinearRegression #导入线性回归模型 x, y = mglearn.datasets.load_extended_boston()x_train, x_test, y_train, y_test = train_test_split(x, y, random_state=0)lr = LinearRegression().fit(x_train, y_train)print("training set score: {:.2f}".format(l...
data_scaled = scaler.fit_transform(data)四、模型构建与训练:实现线性回归 接下来,我们将使用Scikit-learn库构建和训练线性回归模型。通过分割数据集为训练集和测试集,我们可以评估模型在未见过的数据上的表现。from sklearn.model_selection import train_test_split from sklearn.linear_model import Linear...
拟合模型:linear.fit(x,y) 模型的预测值:linear.predict(输入数据) 线性回归模型的权重linear.coef_和偏置linear.intercept_ 三 简单实例 案例1:简单的线性回归器 参考:机器学习算法之线性回归算法(Linear Regression)代码easy_linear_example.py: import numpy as np ...
01 实现Simple Linear Regression 1. 准备数据阶段: import numpy as np import matplotlib.pyplot as plt x = np.array([1., 2., 3., 4., 5.]) y = np.array([1., 3., 2., 3., 5.]) plt.scatter(x, y) plt.axis([0, 6, 0, 6]) ...
#模型训练linear.fit(x_train,y_train) 5)预测 #求出预测值(将测试的特征数据代入predict中)y_pred=linear.predict(x_test) 6)模型评估 #使用r2.score对线性回归模型进行评分fromsklearn.metricsimportr2_score r2_score(y_test,y_pred) 7)绘图
方法一:Scipy.polyfit( ) or numpy.polyfit( )这是一个最基本的最小二乘多项式拟合函数(least squares polynomial fit function),接受数据集和任何维度的多项式函数(由用户指定),并返回一组使平方误差最小的系数。这里给出函数的详细描述。对于简单的线性回归来说,可以选择1维函数。但是如果你想拟合更高维的模型...