Find the closest index with "True" and calculating the distance (Pandas)

Question

I have a DataFrame like this:

idx	Var1	Var2	Var3
0	True	False	False
1	False	True	False
2	True	False	True
3	False	False	False
4	True	False	True

I'd like to create three new columns with the distance (from each row) of the closest True, and if that row has a True show 0, so I would get this:

idx	Var1	Var2	Var3	distV1	distV2	distV3
0	True	False	False	0	1	2
1	False	True	False	1	0	1
2	True	False	True	0	1	0
3	False	False	False	1	2	1
4	True	False	True	0	3	0

I have read all other discussions related to this topic but haven't been able to find an answer for something like this.

Answer 1

Here is one approach with numpy ops:

for c in df:
    r = np.where(df[c])[0]
    d = abs(df.index.values[:, None] - r)
    df[f'{c}_dist'] = abs(df.index - r[d.argmin(1)])

---

print(df)

    Var1   Var2   Var3  Var1_dist  Var2_dist  Var3_dist
0   True  False  False          0          1          2
1  False   True  False          1          0          1
2   True  False   True          0          1          0
3  False  False  False          1          2          1
4   True  False   True          0          3          0