[FIXED] Looping through dataframe with conditions

Issue

This is my input data, which is stored in dataframe df.

Now i want to change all the values in column B to Yearly format. Here is my code:

D = []
for i in df['B']:
    for j in df['C']:
        if j == 'Year':
            D.append(int(i)/1) 
        elif j == 'Month':
            D.append(int(i)/12)
        elif j == 'Day':
            D.append(int(i)/365)

print(len(df))
print(len(D))

While my original df only has len of 10, the output (list D) has len of 100. Anyone knows how to fix the issue here?

Solution

Your code iterates 10 X 10 times because for each i of df['B'] it iterates throughout all the rows of df['C'].

https://pandas.pydata.org/docs/user_guide/basics.html#iteration

D = []
for row in df.itertuples():
   if row.C == 'Year':
      D.append(int(row.B)/1) 
   elif row.C == 'Month':
      D.append(int(row.B)/12)
   elif row.C == 'Day':
      D.append(int(row.B)/365)

Answered By - Raibek