在这个例子中，我如何做“onehot”编码的逆运算？

Question

我有一个熊猫数据集，它有很多列，其中一些列包括：

1. 国家名称
2. 国家代码
3. 指标名称
4. 1960年
5. 1961年
6. 1962年……一直到2015年

我想做的是把所有的年份都放回一列（把1960年到2015年放在一个叫做year的列中）。你知道吗

类似地，在1960-1961等列下，有一些值，我想做的是将这些值设为一个名为values的列。你知道吗

在任务结束时，我希望有这样一个数据集：

1. 国家名称
2. 国家代码
3. 指标名称
4. 年
5. 价值

我知道如何使用get_dummies()工具来“一个热”编码，但我不确定如何使year的那些单个值显示为单个列，并选择代表年份的55列。你知道吗

df = {"country_name": ["Afganistan", "Afganistan", "Afganistan", "Argentina", "Argentina", "Argentina", "Chile","Chile", "Chile", "England", "England", "England", "France", "France", "France", "Germany", "Germany", "Germany", "United States", "United States", "United States", "Bolivia", "Bolivia", "Bolivia"], 
"country_code": ["AFG","AFG","AFG", "ARG","ARG","ARG","CHI","CHI", "CHI","ENG","ENG","ENG","FRA","FRA","FRA","GER","GER","GER","USA", "USA","USA","BOL","BOL","BOL"],
"indicator_name":["adolescent fertility rate", "age dependency ratio", "arms export", "adolescent fertility rate", "age dependency ratio", "arms export", "adolescent fertility rate", "age dependency ratio", "arms export", "adolescent fertility rate", "age dependency ratio", "arms export", "adolescent fertility rate", "age dependency ratio", "arms export", "adolescent fertility rate", "age dependency ratio", "arms export", "adolescent fertility rate", "age dependency ratio", "arms export", "adolescent fertility rate", "age dependency ratio", "arms export"],
1060: [8,5,6, 5,3,9, 11,4,2, 20,17,6, 0,23,17, 8,6,22, 18,14,13, 10,2,8], 
1961: [9,3,9, 6,4,10, 12,5,3, 21,18,7, 1,24,18, 9,7,23, 19,15,14, 11,3,9], 
1962: [10,4,10, 7,5,11, 13,6,4, 22,19,8, 2,25,19, 10,8,24, 20,16,15, 12,4,10]}

以此类推，一直持续到2015年

相关列的结果应该是这样的：

df = {"country_name": ["Afganistan", "Afganistan", "Afganistan", "Afganistan", "Afganistan", "Afganistan", "Afganistan", "Afganistan", "Afganistan", "Argentina", "Argentina", "Argentina", "Argentina", "Argentina", "Argentina", "Argentina", "Argentina", "Argentina", "Chile","Chile", "Chile", "Chile","Chile", "Chile", "Chile","Chile", "Chile", "England", "England", "England", "England", "England", "England", "England", "England", "England", "France", "France", "France", "France", "France", "France", "France", "France", "France", "Germany", "Germany", "Germany", "Germany", "Germany", "Germany", "Germany", "Germany", "Germany", "United States", "United States", "United States", "United States", "United States", "United States", "United States", "United States", "United States", "Bolivia", "Bolivia", "Bolivia", "Bolivia", "Bolivia", "Bolivia", "Bolivia", "Bolivia", "Bolivia"], 
"country_code": ["AFG","AFG","AFG", "AFG","AFG","AFG", "AFG","AFG","AFG", "ARG","ARG","ARG", "ARG","ARG","ARG", "ARG","ARG","ARG", "CHI","CHI", "CHI", "CHI","CHI", "CHI", "CHI","CHI", "CHI","ENG","ENG","ENG", "ENG","ENG","ENG", "ENG","ENG","ENG","FRA","FRA","FRA", "FRA","FRA","FRA","FRA","FRA","FRA", "GER","GER","GER", "GER","GER","GER", "GER","GER","GER", "USA", "USA","USA", "USA", "USA","USA", "USA", "USA","USA", "BOL","BOL","BOL", "BOL","BOL","BOL", "BOL","BOL","BOL"],
"indicator_name":["adolescent fertility rate", "adolescent fertility rate","adolescent fertility rate","age dependency ratio","age dependency ratio","age dependency ratio","arms export","arms export", "arms export", "adolescent fertility rate", "adolescent fertility rate","adolescent fertility rate","age dependency ratio","age dependency ratio","age dependency ratio","arms export","arms export","arms export", "adolescent fertility rate", "adolescent fertility rate","adolescent fertility rate","age dependency ratio","age dependency ratio","age dependency ratio","arms export","arms export","arms export", "adolescent fertility rate", "adolescent fertility rate","adolescent fertility rate","age dependency ratio","age dependency ratio","age dependency ratio","arms export","arms export","arms export", "adolescent fertility rate", "adolescent fertility rate","adolescent fertility rate","age dependency ratio","age dependency ratio","age dependency ratio","arms export","arms export","arms export","adolescent fertility rate", "adolescent fertility rate","adolescent fertility rate","age dependency ratio","age dependency ratio","age dependency ratio","arms export","arms export","arms export", "adolescent fertility rate", "adolescent fertility rate","adolescent fertility rate","age dependency ratio","age dependency ratio","age dependency ratio","arms export","arms export","arms export", "adolescent fertility rate", "adolescent fertility rate","adolescent fertility rate","age dependency ratio","age dependency ratio","age dependency ratio","arms export","arms export","arms export"],
"year": [1960, 1960, 1960, 1961, 1961, 1961, 1962, 1962, 1962, 1960, 1960, 1960, 1961, 1961, 1961, 1962, 1962, 1962, 1960, 1960, 1960, 1961, 1961, 1961, 1962, 1962, 1962, 1960, 1960, 1960, 1961, 1961, 1961, 1962, 1962, 1962, 1960, 1960, 1960, 1961, 1961, 1961, 1962, 1962, 1962, 1960, 1960, 1960, 1961, 1961, 1961, 1962, 1962, 1962, 1960, 1960, 1960, 1961, 1961, 1961, 1962, 1962, 1962, 1960, 1960, 1960, 1961, 1961, 1961, 1962, 1962, 1962],
"value": [8,5,6,9,3,9,10,4,10,  5,3,9,6,4,10,7,5,11,  11,4,2,12,5,3,13,6,4,  20,17,6,21,18,7,22,19,8,  0,23,17,1,24,18,2,25,19,  8,6,22,9,7,23,10,8,24,  18,14,13,19,15,14,20,16,15, 10,2,8,11,3,9,12,4,10] 
}