Convert a dataframe to list of tuples [duplicate]

Question

I have a python pandas dataframe df like this:

a  b
1  3
3  6
5  7
6  4
7  8

I want to transfer it to a list:

[(1,3),(3,6),(5,7),(6,4),(7,8)]

Thanks.

Answer 1

If performance is important, use a list comprehension:

[tuple(r) for r in df.to_numpy()]
# [(1, 3), (3, 6), (5, 7), (6, 4), (7, 8)]

Note: For pandas < 0.24, please use df.values instead.

You may find even better performance if you iterate over lists instead of the numpy array:

[tuple(r) for r in df.to_numpy().tolist()]
# [(1, 3), (3, 6), (5, 7), (6, 4), (7, 8)]

This method to any number of columns. However, if you want to select a specific set of columns to convert, you can select them beforehand.

[tuple(r) for r in df[['a', 'b']].to_numpy()]
# [(1, 3), (3, 6), (5, 7), (6, 4), (7, 8)]

---

Another alternative is using map.

list(map(tuple, df.to_numpy()))
# [(1, 3), (3, 6), (5, 7), (6, 4), (7, 8)]

This is roughly the same as the list comprehension, performance wise. You can generalise the same way.

---

Another option is to use apply and convert the result to a list:

df.apply(tuple, axis=1).tolist()
# [(1, 3), (3, 6), (5, 7), (6, 4), (7, 8)]

This is slower, so it not recommended.

Answer 2

Use zip() to create tuples

df = pd.DataFrame({'a':[1,3,5,6,7], 'b':[3,6,7,4,8]})
print(list(zip(df['a'], df['b']))

Answer 3

You can also get the desired list like that:

zip(list(df['a']), list(df['b']))