pandas 여러열적용

df[cols] = df[cols].astype(float).fillna(0).astype(int)

cols = ['A', 'B', 'C', 'D']  # 변환하고 싶은 열 이름들
for col in cols:
    df[col] = pd.to_numeric(df[col], errors='coerce').fillna(0).astype(int)
    
df[cols] = df[cols].apply(pd.to_numeric, errors='coerce').fillna(0).astype(int)

예제

import pandas as pd

# 샘플 데이터프레임 생성
data = {
    'A': ['1', '2', '3', '4', ''],
    'B': ['5', '6', '7', '8', 'abc'],
    'C': ['9', '10', '11', '12', ''],
    'D': ['13', '14', '15', '16', 'def']
}

df = pd.DataFrame(data)
print(df)

     A    B     C     D
0    1    5     9    13
1    2    6    10    14
2    3    7    11    15
3    4    8    12    16
4         abc         def

cols = ['A', 'B', 'C', 'D']
df[cols] = df[cols].apply(pd.to_numeric, errors='coerce').fillna(0).astype(int)
print(df)

   A  B   C   D
0  1  5   9  13
1  2  6  10  14
2  3  7  11  15
3  4  8  12  16
4  0  0   0   0