create a dataframe with dataframes of different sizes

Question

I have a dataframe and two array with differents sizes and i want to create a single dataframe

for example

import pandas
import numpy

 df = pandas.DataFrame(numpy.array([[0,0,1]]),columns = ['A', 'B', 'C'])
  V1=numpy.array([0,1,3,4])
  V2=numpy.array([2,3,5,8,11,12])

I want obtain a single dataframe like :

  A  B  C V1 V2
  0  0  1 0   2
  0  0  1 1   3
  0  0  1 3   5
  0  0  1 4   8   
  0  0  1 Nan 11
  0  0  1 Nan 12

https://stackoverflow.com/questions/18646076/add-numpy-array-as-column-to-pandas-data-frame: Chk this — Rahul Agarwal, Apr 02 '19 at 13:23

jezrael · Accepted Answer · 2019-04-02T13:34:11.393

First is necessary repeat array in first DataFrame by maximum length of array, then create for each array Series and join together by concat:

a = [V1, V2]
n = max(map(len, a))
df1 = pd.DataFrame(np.array(np.repeat([[0,0,1]], n, axis=0)), columns = ['A', 'B', 'C'])
df = pd.concat([df1, pd.Series(V1, name='V1'), pd.Series(V2, name='V2')], axis=1)
print (df)
   A  B  C   V1  V2
0  0  0  1  0.0   2
1  0  0  1  1.0   3
2  0  0  1  3.0   5
3  0  0  1  4.0   8
4  0  0  1  NaN  11
5  0  0  1  NaN  12

create a dataframe with dataframes of different sizes

1 Answers1