Pandas / 如何将存储为字符串的科学记数法转换为浮点数？

Question

I have a list with values stored as strings. Some of the values are stored with scientific notation and others are floats. I tried to cast them using .astype(float) but It didn't work. Any idea on how to deal with this?

My goal is to get the column as float.

df['Colum1] = ['5,4e-05','3,35e-05','0,0001125','0,0001335']

Answer 1

First you have to replace the commas for dots, then you can just cas to float :

df.Colum1.str.replace(',', '.').astype(float)

Also to prevent from any errors, pd.to_numeric is probably the best option:

pd.to_numeric(df.Col1.str.replace(',', '.'), errors='coerce')

---

Here's an example:

df = pd.DataFrame({'Col1':['5,4e-05','3,35e-05','0,0001125','0,0001335']})

pd.to_numeric(df.Col1.str.replace(',', '.'), errors='coerce')

0    0.000054
1    0.000034
2    0.000112
3    0.000133
Name: Col1, dtype: float64