使用 pandas 将列表列表写入现有 csv 文件

Question

I want to add values from a list pair1 to a new column with the corresponding name.

pair1 = [['ab','bc','cd'],['cd','de','ef'],['sa','hg','gh','de']]

I am using pandas to add a new column to the csv file but inserting a whole list into a single cell is throwing error. If I use zip(pr1), it is inserting the index position of the zip file.

csv_source_1 = pd.read_csv('D:\\Python 
Automation\\Rough\\Source_1.csv',error_bad_lines=False)
pair1 = [['ab','bc','cd'],['cd','de','ef'],['sa','hg','gh','de']]
for pr1 in pair1:
        csv_source_1['pair1'] = pr1
csv_source_1.to_csv('D:\\Python Automation\\Rough\\Source_1.csv')

I am looking for below as output:

eid ename     pairs
1   james    'ab','bc','cd'
2   thomas   'cd','de','ef'

The error I receive is:

ValueError: Length of values does not match length of index

Answer 1

Replace the for loop with below

pair1 = [['ab','bc','cd'],['cd','de','ef'],['sa','hg','gh','de']]

csv_source_1['pair1'] = pd.Series(pair1)
csv_source_1['pair1'] = csv_source_1['pair1'].map(lambda x: ",".join(x))

csv_source_1.to_csv('D:\\Python Automation\\Rough\\Source_1.csv')