Creating pandas DataFrame from a list of objects and manipulating over these objects

Question

I have a list of 5 matrices:

import numpy as np
import pandas as pd
a=[(np.random.randint(2,size=(2,3))) for i in xrange(5)]

How do I create a pandas DataFrame of 5 records with a single column containing a matrrix for each row?

Bharath M Shetty · Accepted Answer · 2017-07-02 10:36:45Z

2

You can create the dataframe by running :

df= pd.DataFrame({'array':a})

Output :

   array
0  [[0, 0, 0], [0, 0, 0]]
1  [[0, 1, 1], [0, 0, 0]]
2  [[1, 0, 0], [0, 1, 1]]
3  [[1, 0, 1], [1, 0, 0]]
4  [[0, 0, 0], [0, 0, 1]]

If you want to apply cumsum over the column you can use apply

df['array']=df['array'].apply(np.cumsum)

output:

                array
0  [0, 0, 0, 0, 0, 0]
1  [0, 1, 2, 2, 2, 2]
2  [1, 1, 1, 1, 2, 3]
3  [1, 1, 2, 3, 3, 3]
4  [0, 0, 0, 0, 0, 1]

answered Jul 2, 2017 at 9:52

Bharath M Shetty

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1 Comment

Updated my answer