如何在数据框上添加一列以求和

Question

我想在数据框中添加一列，以便求和相应行中所有值的总和

例如：

1  2       Column I Want to Add

4  9                13
7  1                8

Answer 1

您可以df.sum(axis = 1)，这将创建一个新列（而不是一行）：

import pandas as pd
df = pd.DataFrame({1: [4, 7], 2: [9, 1]})

df['COLUMN I Want to Add'] = df.sum(axis = 1)
print(df)

输出：

   1  2  COLUMN I Want to Add
0  4  9                    13
1  7  1                     8

Answer 2

public static IEnumerableExt { public static List<MemberInfo> GetPropertiesOrFields(this Type t, BindingFlags bf = BindingFlags.Public | BindingFlags.Instance) => t.GetMembers(bf).Where(mi => mi.MemberType == MemberTypes.Field || mi.MemberType == MemberTypes.Property).ToList(); public static DataTable ToDataTable<T>(this IEnumerable<T> rows) { var dt = new DataTable(); if (rows.Any()) { var memberInfos = typeof(T).GetPropertiesOrFields(); foreach (var info in memberInfos) dt.Columns.Add(new DataColumn(info.Name, info.GetMemberType())); foreach (var r in rows) dt.Rows.Add(memberInfos.Select(i => i.GetValue(r)).ToArray()); } return dt; } }