根据另一列的单元格值从一列获取单元格值

Question

我有这个数据框

d = {'Number': [1, 2,3,4,5,6,7], 'Letters': ["a", "d","z","f","u","p","g"]}
df = pd.DataFrame(data=d)

    Number Letters
0       1       a
1       2       d
2       3       z
3       4       f
4       5       u
5       6       p
6       7       g

我想基于Letters列从Number列中获取一个值 可以说我想得到数字为3的字母

我所做的是

letter = df.loc[df['Number'] == 3]
dfletter = pd.DataFrame(data=letter.values, columns = ['Number', 'Letter']) 
dfletter = dfletter.drop(columns = 'Number')

这给了我我想要的东西

    Letter
0      z

但这似乎是一个愚蠢的解决方法，所以我正在寻找更好的解决方案

Answer 1

output = df.loc[df['Number'] == 3, 'Letters']

Answer 2

>>> df[df.Number == 3].Letters
2    z
Name: Letters, dtype: object

或者，如果您确实需要标量值：

>>> df[df.Number == 3].Letters.values[0]
'z'