Trying to convert currency in a df using python. I have two columns: price and currency. I tried to use if/elif/else statements but I'm doing something wrong.

Sample of df: 
|price|currency|boat type| year built|
|-----|--------|---------|-----------|
|3490 |EUR     |console  | 2020      |
|2299 |EUR     |fishing  | 2019      |
|3500 |CHF     |fishing  | 1987      |
|4600 |£      |runabout | 2020      |

Any suggestions are appreciated. Thank you

Code I've tried...

if drop_boats['Currency'] == 'EUR':
    drop_boats['Price'] = drop_boats['Price'] * 1.10 
elif drop_boats['Currency'] == 'CHF':
    drop_boats['Price'] = drop_boats['Price'] * 1.08 
elif drop_boats['Currency'] == 'DKK':
    drop_boats['Price'] = drop_boats['Price'] * 0.15 
elif drop_boats['Currency'] == '£':
    drop_boats['Price'] = drop_boats['Price'] * 1.32
else:
     drop_boats['Price' ]= drop_boats['Price']

I'm getting this error: ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().

CodePudding user response：

You can iter over the pandas rows using iter.rows() and carry the calculation. Refer the below code:

for index, row in df.iterrows():
    if row['Currency'] == 'EUR':
        row['Price'] = row['Price'] * 1.10 
    elif row['Currency'] == 'CHF':
        row['Price'] = row['Price'] * 1.08 
    elif row['Currency'] == 'DKK':
        row['Price'] = row['Price'] * 0.15 
    elif row['Currency'] == '£':
        row['Price'] = row['Price'] * 1.32
    else:
        row['Price' ]= row['Price']

CodePudding user response：

You probably want loc with boolean indexing. If not show sample input and output data, please.

drop_boats.loc[drop_boats['Currency'].eq('EUR'), 'Price'] *= 1.10

CodePudding user response：

One way to accomplish what you want is like this:

for index, row in drop_boats.iterrows():
  if row['Currency'] == 'EUR':
    drop_boats.loc[index, 'Price'] = row['Price'] * 1.10

You can add your other conditions accordingly...