Let’s assume I have the following dataframe:

```
import pandas as pd
d = {'col1': [1, 2,3,4], 'col2': [4, 2, 1, 3], 'col3': [1,0,1,1], 'outcome': [1,0,1,0]}
df = pd.DataFrame(data=d)
```

I want this dataframe sorted by col1 and col2 on the minimum value. The order of the indexes should be 2, 0, 1, 3.

I tried this with `df.sort_values(by=['col2', 'col1'])`

, but than it takes the minimum of col1 first and then of col2. Is there anyway to order by taking the minimum of two columns?

### >Solution :

Using `numpy.lexsort`

:

```
order = np.lexsort(np.sort(df[['col1', 'col2']])[:, ::-1].T)
out = df.iloc[order]
```

Output:

```
col1 col2 col3 outcome
2 3 1 1 1
0 1 4 1 1
1 2 2 0 0
3 4 3 1 0
```

Note that you can easily handle any number of columns:

```
df.iloc[np.lexsort(np.sort(df[['col1', 'col2', 'col3']])[:, ::-1].T)]
col1 col2 col3 outcome
1 2 2 0 0
2 3 1 1 1
0 1 4 1 1
3 4 3 1 0
```