val courseNames = all_Data.head.drop(2)这段代码什么意思

这段代码的意思是从 all_Data 列表中取出第一个元素（即列表），然后去掉前两个元素（即第一列和第二列），得到一个新的列表 courseNames，该列表包含了 all_Data 中除第一列和第二列以外的所有列的名称。

相关问题

val courseNames = all_Data.head.drop(2)如何改进

这段代码可以改进为使用更具有可读性的变量名，例如：

val courseNames = allData.head.drop(2)

可以改为：

val courseNames = allData.firstRow.dropFirstTwoColumns()

这样可以更清晰地表达代码的意图，提高代码的可读性和可维护性。

import pandas as pd from sklearn.model_selection import train_test_split from sklearn.ensemble import RandomForestClassifier from sklearn.preprocessing import OneHotEncoder,LabelEncoder from sklearn.model_selection import cross_val_score from sklearn.model_selection import GridSearchCV df = pd.read_csv('mafs(1).csv') df.head() man = df['Gender']=='M' woman = df['Gender']=='F' data = pd.DataFrame() data['couple'] = df.Couple.unique() data['location'] = df.Location.values[::2] data['man_name'] = df.Name[man].values data['woman_name'] = df.Name[woman].values data['man_occupation'] = df.Occupation[man].values data['woman_occupaiton'] = df.Occupation[woman].values data['man_age'] = df.Age[man].values data['woman_age'] = df.Age[woman].values data['man_decision'] = df.Decision[man].values data['woman_decision']=df.Decision[woman].values data['status'] = df.Status.values[::2] data.head() data.to_csv('./data.csv') data = pd.read_csv('./data.csv',index_col=0) data.head() enc = OneHotEncoder() matrix = enc.fit_transform(data['location'].values.reshape(-1,1)).toarray() feature_labels = enc.categories_ loc = pd.DataFrame(data=matrix,columns=feature_labels) data_new=data[['man_age','woman_age','man_decision','woman_decision','status']] data_new.head() lec=LabelEncoder() for label in ['man_decision','woman_decision','status']: data_new[label] = lec.fit_transform(data_new[label]) data_final = pd.concat([loc,data_new],axis=1) data_final.head() X = data_final.drop(columns=['status']) Y = data_final.status X_train,X_test,Y_train,Y_test=train_test_split(X,Y,train_size=0.7,shuffle=True) rfc = RandomForestClassifier(n_estimators=20,max_depth=2) param_grid = [ {'n_estimators': [3, 10, 30,60,100], 'max_features': [2, 4, 6, 8], 'max_depth':[2,4,6,8,10]}, ] grid_search = GridSearchCV(rfc, param_grid, cv=9) grid_search.fit(X, Y) print(grid_search.best_score_) #最好的参数 print(grid_search.best_params_)

这段代码是使用随机森林分类器对一个约会节目的参赛者进行分类的，根据他们的年龄、职业、决策等信息，将他们的状态（是否找到约会对象）进行预测。代码中使用了OneHotEncoder和LabelEncoder对分类变量进行编码，使用GridSearchCV对超参数进行调优。最后输出了最好的参数和相应的得分。