pandas ValueError：无法将字符串转换为浮点数：'4,6'
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ValueError: could not convert string to float: '4,6'
提问by mohamoud wueza
While reading from csv I have ValueError: could not convert string to float. It begins from readng the file, after I give names to columns and remove NaNs.
从 csv 读取时，我有ValueError: could not convert string to float. 它从读取文件开始，在我为列命名并删除 NaN 之后。
from pandas import read_csv
df = read_csv("propositio/data.csv", header=None,
sep=';', decimal=',')
cols = ['col1', 'col2', 'col3', 'col4']
df.columns = cols
df.dropna(inplace=True)
Here comes an error. I want to convert non-null objectinto floats:
这里出现了一个错误。我想转换non-null object成浮点数：
df = df.astype(float)
ValueError: could not convert string to float: '4,6'
ValueError：无法将字符串转换为浮点数：'4,6'
How can I fix it?
我该如何解决？
回答by Rakesh
Use str.replaceto replace comma with dot
用于str.replace用点代替逗号
Ex:
前任：
import pandas as pd
df = pd.DataFrame({"A": ['4,6', "5.6", '6,6']})
df = df["A"].str.replace(',', ".").astype(float)
print(df)
Output:
输出：
0 4.6
1 5.6
2 6.6
Name: A, dtype: float64
