Convert multi-dim list in one column in python pandas

Question

I would like to know whether I can get some help in "translating" a multi dim list in a single column of a frame in pandas.

I found help here to translate a multi dim list in a column with multiple columns, but I need to translate the data in one

Suppose I have the following list of list

x=[[1,2,3],[4,5,6]]

If I create a frame I get

frame=pd.Dataframe(x)

0  1  2
1  2  3
4  5  6

But my desire outcome shall be

0
1
2
3
4
5
6

with the zero as column header.

I can of course get the result with a for loop, which from my point of view takes much time. Is there any pythonic/pandas way to get it?

Thanks for helping men

Answer 1

You can use np.concatenate

x=[[1,2,3],[4,5,6]]

frame=pd.DataFrame(np.concatenate(x))
print(frame)

Output:

    0
0   1
1   2
2   3
3   4
4   5
5   6

Answer 2

First is necessary flatten values of lists and pass to DataFrame constructor:

df = pd.DataFrame([z for y in x for z in y])

Or:

from  itertools import chain

df = pd.DataFrame(list(chain.from_iterable(x)))

---

print (df)
   0
0  1
1  2
2  3
3  4
4  5
5  6

Answer 3

If you use numpy you can utilize the method ravel():

pd.DataFrame(np.array(x).ravel())