用pandas Python将str转换为float

Question

I need to change all my column data from str to float but the problema is I have numbers and '--' too. I want to change all '--' to a 0.00 and then my objetivo variable could be work.

import pandas as pd
df = pd.read_csv('status.csv')    
objetivo = df['BP Booked Imps Budget (lifetime)'].astype(float)

error: ValueError: could not convert string to float: --

csv:

BP Booked Imps Budget (lifetime), Imp
--,5555444
--,342345
--,245632
--,2345467
21345,3456
1234,34567
456,324567
123456,7654
--,6543

Answer 1

Along the lines of what you're already doing, you could do

df['BP Booked Imps Budget (lifetime)'].replace('--', 0).astype(float)

A different approach would be

pd.to_numeric(df['BP Booked Imps Budget (lifetime)'], errors='coerce').fillna(0)

Answer 2

As I understand it,

df['BP Booked Imps Budget (lifetime)'] = df['BP Booked Imps Budget (lifetime)'].apply(lambda x: 0.0 if x == '--' else x)
df['objectivo'] = df['BP Booked Imps Budget (lifetime)'].astype(float)