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Convert lists to dataframe, where list elements are column headers, and rows represent a binary response if list had element

byMR

November 22, 2023

I have multiple lists, and want to convert them to a dataframe

ss1 = ['a','b','c'] 
ss2 = ['d','c','b','a','f']
ss3 = ['a','g']
ss4 = ['a','d','g','h']
ls=[ss1,sorted(ss2),sorted(ss3),ss4]
pd.DataFrame(ls)

but, I want the distinct individual elements of the combined lists as the column headers, and a 1/0 response in the body showing whether or not that column header (element) was in that row (list)

I want:

pd.DataFrame({'a':[1,1,1,1],
              'b':[1,1,None,None],
              'c':[1,1,None,None],
              'd':[None,1,None,1],
              'f':[None,None,1,None],
              'g':[None,None,1,1],
              'h':[None,None,None,1]})

Visually, from:

>Solution :

You could rework the list into a list of dictionaries with dict.fromkeys:

out = pd.DataFrame([dict.fromkeys(x, 1) for x in ls])

Output:

   a    b    c    d    f    g    h
0  1  1.0  1.0  NaN  NaN  NaN  NaN
1  1  1.0  1.0  1.0  1.0  NaN  NaN
2  1  NaN  NaN  NaN  NaN  1.0  NaN
3  1  NaN  NaN  1.0  NaN  1.0  1.0