defload_exdata(filename):data=[]withopen(filename,'r')asf:forlineinf.readlines():line=line.split(',')current=[int(item)foriteminline]#5.5277,9.1302data.append(current)returndata data=load_exdata('ex1data2.txt');data=np.array(data,np.int64)x=data[:,(0,1)].reshape((-1,2))y=dat...
这个时候特征缩放就很重要 梯度下降 线性回归的python代码 # -*- coding=utf8 -*- import math; def sum_of_gradient(x, y, thetas): """计算梯度向量,参数分别是x和y轴点坐标数据以及方程参数""" m = len(x); grad0 = 1.0 / m * sum([(thetas[0] + thetas[1] * x[i] - y[i]) for...
Symbolic Linear Regression for two variablesOldemar Rodriguez Rojas
§ 2. 多变量线性回归 Linear Regression with Multiple Variables 1 多特征值(多变量) Multiple Features(Variables) 首先,举例说明了多特征值(多变量)的情况。在下图的例子中,x1,x2,x3,x4x1,x2,x3,x4都是输入的变量,因为变量个数大于一,所以也称为多变量的情况。 于是引出多变量线性回归的一般假设形式: 2...
其中:ℎ𝜃(𝑥) = 𝜃𝑇𝑋 = 𝜃0 + 𝜃1𝑥1 + 𝜃2𝑥2+. . . +𝜃𝑛𝑥𝑛 ,我们的目标和单变量线性回归问题中一样,是要找出使得代价函数最小的一系列参数。多变量线性回归的批量梯度下降算法为: 即: 求导数后得到:
Linear regression, in statistics, a process for determining a line that best represents the general trend of a data set. The simplest form of linear regression involves two variables: y being the dependent variable and x being the independent variable. T
【Machine Learning】4 多变量线性回归(Linear Regression with Multiple Variables),程序员大本营,技术文章内容聚合第一站。
Linear Regression with Multiple Variables. 1. Multivariate Linear Regression I would like to give full credits to the respective authors as these are my personal python notebooks taken from deep learning courses from Andrew Ng, Data School and Udemy :) This is a simple python notebook hosted ...
Linear Regression with multiple variables - Gradient descent in practice I: Feature Scaling 摘要: 本文是吴恩达 (Andrew Ng)老师《机器学习》课程,第五章《多变量线性回归》中第30课时《多元梯度下降法实践 I: 特征缩放》的视频原文字幕。为本人在视频学习过程中记录下来并加以修正,使其更加简洁,方便阅读,以便日...
[Section 2] Gradient Descent for Multiple Variables [Section 3] Gradient Descent in Practice I - Feature Scaling [Section 4] Gradient Descent in Practice II - Learning Rate [Section 5] Features and Polynomial Regression [Section 6] Normal Equation ...