pemahaman daftar panda
# Subtract 1 from row, for each row in df.year
df['previous_year'] = [row-1 for row in df['year']]
Magnificent Mole
# Subtract 1 from row, for each row in df.year
df['previous_year'] = [row-1 for row in df['year']]
df['Flag'] = ["High Bracket" if x > 70 else "Low Bracket" for x in df['prevsalary']]
mat = [[1,2], [3,4], [5,6]]
[x for row in mat for x in row if x%2==1]
df['Flag2'] = ["Increase" if x > y else "Decrease" for (x,y) in zip(df['nextsalary'],df['prevsalary'])]