如何根据字典条件重新排序 pandas 数据框

Question

我有一个这样的df，

    case        step    deep                   value
0   case 1      1       ram in India           ram,cricket
1   NaN         2       ram plays cricket       NaN
2   case 2      1       ravi played football   ravi
3   NaN         2       ravi works welll        NaN
4   case 3      1       Sri bought a car       sri
5   NaN         2       sri went out            NaN

还有一本字典，my_dict = {ram:1,cricket:1,ravi:2.5,sri:1}

我正在尝试根据字典的值重新排序数据帧，我使用 tfidf 方法实现了这个字典。我在重新排序时遇到困难，因为我们需要重新排序包含值的行。

我的预期输出是，

    case        step    deep                   value
2   case 2      1       ravi played football   ravi
3   NaN         2       ravi works welll        NaN
0   case 1      1       ram in India           ram,cricket
1   NaN         2       ram plays cricket       NaN
4   case 3      1       Sri bought a car       sri
5   NaN         2       sri went out            NaN

请帮忙，提前致谢！

Answer 1

您可以创建 MultiIndex 进行排序，只有 value 列的必要值在 my_dict:

中

my_dict = {'ram':1,'cricket':1,'ravi':2.5,'sri':1}

#create DataFrame from value column, replace and sum columns
a = df['value'].str.split(',', expand=True).replace(my_dict).sum(axis=1)
#create groups
b = df['step'].diff().le(0).cumsum()
#create Series by summing per groups
c = a.groupby(b).transform('sum')
#create MultiIndex
df.index = [c,b]
print (df)
            case  step                  deep        value
    step                                                 
2.0 0     case 1     1          ram in India  ram,cricket
    0        NaN     2     ram plays cricket          NaN
2.5 1     case 2     1  ravi played football         ravi
    1        NaN     2      ravi works welll          NaN
1.0 2     case 3     1      Sri bought a car          sri
    2        NaN     2          sri went out          NaN

#sorting MultiIndex and removing
df = df.sort_index(ascending=False).reset_index(drop=True)
print (df)
     case  step                  deep        value
0  case 2     1  ravi played football         ravi
1     NaN     2      ravi works welll          NaN
2  case 1     1          ram in India  ram,cricket
3     NaN     2     ram plays cricket          NaN
4  case 3     1      Sri bought a car          sri
5     NaN     2          sri went out          NaN

如何根据字典条件重新排序 pandas 数据框

how to re order a pandas dataframe based on a dictionary condition

python

data-analysis

scipy

dataframe

pandas