How to append value in column with python pandas

Question

I am trying to append new values in column with pandas. This is data frame example: code:

data = pd.read_csv('data/email.csv', sep=";")
data.insert(0,'imgid','')
print(data)

result:

  imgid              email    id  fname    lname
0        [email protected]  2070  Laura     Grey
1        [email protected]  4081  Craig  Johnson
2         [email protected]  9346   Mary  Jenkins
3        [email protected]  5079  Jamie    Smith

And then I have this code:

import os
for root, dirs, files in os.walk("data/"):
    for file in files:
        if file.endswith(".jpg"):
            img = file.split('.')[0]
            print(file, " is ", img)

result:

2070.jpg  is  2070
4081.jpg  is  4081
5079.jpg  is  5079
9346.jpg  is  9346

As a final result I want to compare data['id'] to img and if they are equal, add img's full file name in data["imgid"].

Is there any simple way to do that , I mean not to load memory too much. Thanks

Answer 1

You can try this:

import os

lst = []
for root, dirs, files in os.walk("data/"):
    for file in files:
        if file.endswith(".jpg"):
            img = file.split('.')[0]
            lst.append([img,file])

np_arr = np.array(lst)
bool_arr = (df["num_wings"] == np_arr[:,0])
data.loc[bool_arr,"imgid"] = np_arr[bool_arr,1]