0. 使用 PCA 降维
matlab:
[coeff, score] = pca(A); reducedDimension = coeff(:,1:5); reducedData = A * reducedDimension;
1. 最大最小映射(matlab)
[trainx, s1] = mapminmax(trainx);
testx = mapminmax('apply', test1, s1);
2. sklearn.preprocessing
去均值时,在测试集上进行预测时减去的均值是训练集上得到的均值;
import sklearn.preprocessing as prep
def standard_scale(X_train, X_test):
preprocessor = prep.StandardScaler().fit(X_train)
X_train = preprocessor.transform(X_train)
X_test = preprocessor.transform(X_test)
return X_train, X_test