Should I use pandas dictionary? How?-CodePudding

I have a data frame like this:

Code
DA
DB
DC
DD
DE
DF
DG
DX
DY
DZ

And I want to add a column to the table above so that each value in the code column has a fixed value like the table below:

Code	Value
DA	A
DB	A
DC	A
DD	B
DE	B
DF	B
DG	C
DX	C
DY	C

How should I do this ??

CodePudding user response：

df = pd.DataFrame( {'Code': ['DA', 'DB', 'DC', 'DD', 'DE', 'DF', 'DG', 'DX', 'DY']} )
dct = {'DA': 'A', 'DB': 'A', 'DC': 'A',
       'DD': 'B', 'DE': 'B', 'DF': 'B',
       'DG': 'C', 'DX': 'C', 'DY': 'C'}
df['Value'] = df['Code'].replace(dct)
print(df)

Prints:

  Code Value
0   DA     A
1   DB     A
2   DC     A
3   DD     B
4   DE     B
5   DF     B
6   DG     C
7   DX     C
8   DY     C

CodePudding user response：

try this:

Value = ['A', 'A', 'A', 'B', 'B', 'B', 'C', 'C', 'C']
df['Value'] = Value