我是机器学习领域的初学者,目前遇到了一个问题,急需帮助。我有一个数据集,包含州名、月份、温度和降雨量。我的代码是:
import pandas as pdimport numpy as npimport matplotlib.pyplot as pltdata=pd.read_csv('cropdata.csv')x=data.iloc[:, :-1].valuesy=data.iloc[:, 4].valuesdistrict = pd.get_dummies(data['District'],drop_first = False)month = pd.get_dummies(data['Month'],drop_first = False)crop = pd.get_dummies(data['Crop'],drop_first = False)data= pd.concat([data,district],axis=1)data.drop('District', axis=1,inplace=True)data= pd.concat([data,month],axis=1)data.drop('Month', axis=1,inplace=True)data= pd.concat([data,crop],axis=1)data.drop('Crop', axis=1,inplace=True)print(data.head(1))train=data.iloc[:, 0:44].valuestest=data.iloc[: ,44:].valuesfrom sklearn.preprocessing import Imputerimputer1 = Imputer(missing_values = 'NaN', strategy = 'mean', axis = 0)imputer1 = imputer1.fit(train[:, 0:44])train[:, 0:44] = imputer1.transform(train[:, 0:44])from sklearn.model_selection import train_test_splitX_train,X_test,y_train,y_test=train_test_split(train,test,test_size=0.3)from sklearn.preprocessing import StandardScalersc = StandardScaler()X_train = sc.fit_transform(X_train)X_test = sc.transform(X_test)from sklearn.tree import DecisionTreeRegressorfrom sklearn.datasets import load_irisclf=DecisionTreeRegressor(max_depth = 19,random_state = None)#Fitting the classifier into training setclf.fit(X_train,y_train)pred=clf.predict(X_test)print(pred)predx=pred.round()from sklearn.metrics import accuracy_score# Finding the accuracy of the modela=accuracy_score(y_test,pred.round())print("The accuracy of this model is: ", a*100)from sklearn import treeiris = load_iris()clf = clf.fit(iris.data, iris.target)plt.figure(figsize=(10,10))tree.plot_tree(clf);
模型的准确率为70%,但出现了以下错误:
ValueError: x和y的第一维度必须相同,但它们的形状分别为(4536, 44)和(1944, 12)
现在我不明白该如何解决这个错误,以及如何从这个问题中绘制图表?
回答:
根据你的错误信息,你的X_train数据包含4536行用于训练数据集,这意味着每行都有自己的目标值(标签),因此标签值应该为4536(y_train)
但你的y_train仅包含1944个标签,这与X_train所需的标签不匹配
每个X_train都需要对应的标签,你提供了一些标签,而其余的则是未标记的