I have a data set that had values entered incorrectly such that the scale needed is 0-4 but it was entered as 0-5, what is the best way to scale down data such as the following table:
| a | b | c |
|---|---|---|
| 0 | 2 | 5 |
| 5 | 4 | 3 |
| 1 | 4 | 2 |
| 3 | 4 | 0 |
CodePudding user response：
If you want to scale all values in your df, you can use
df = df*4/5
a b c
0 0.0 1.6 4.0
1 4.0 3.2 2.4
2 0.8 3.2 1.6
3 2.4 3.2 0.0
recreating your input:
df = pd.DataFrame({'a': {0: 0, 1: 5, 2: 1, 3: 3}, 'b': {0: 2, 1: 4, 2: 4, 3: 4}, 'c': {0: 5, 1: 3, 2: 2, 3: 0}})
CodePudding user response：
without assuming the the maximum value is 5, you can extract the maximum value and apply the scale down based on it:
df = df / df.max().max() * 4
print(df)
input
a b c
2 5 5
8 4 3
1 4 2
3 4 0
output
a b c
1.0 2.5 2.5
4.0 2.0 1.5
0.5 2.0 1.0
1.5 2.0 0.0