莫烦python教程学习笔记——数据预处理之normalization
# View more python learning tutorial on my Youtube and Youku channel!!! # Youtube video tutorial: https://www.youtube.com/channel/UCdyjiB5H8Pu7aDTNVXTTpcg # Youku video tutorial: http://i.youku.com/pythontutorial """ Please note, this code is only for python 3+. If you are using python 2+, please modify the code accordingly. """ from __future__ import print_function from sklearn import preprocessing import numpy as np from sklearn.model_selection import train_test_split from sklearn.datasets.samples_generator import make_classification from sklearn.svm import SVC import matplotlib.pyplot as plt #手动构造的数据并对其进行归一化,即减去均值,除以方差,使其数据在同一度量范围内 a = np.array([[10, 2.7, 3.6], [-100, 5, -2], [120, 20, 40]], dtype=np.float64) print(a) print(preprocessing.scale(a))
#对sklearn自动生成的数据集对其进行归一化,绘制散点图 X, y = make_classification(n_samples=300, n_features=2 , n_redundant=0, n_informative=2, random_state=22, n_clusters_per_class=1, scale=100) plt.scatter(X[:, 0], X[:, 1], c=y) plt.show() X = preprocessing.scale(X) # normalization step X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=.3) clf = SVC() clf.fit(X_train, y_train) print(clf.score(X_test, y_test))