Why Doesn't Python Recognize the Column Name (KeyError)

Rhoomesie 0
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I imported stock/options data into a data frame and want to use pandas to manually filter for specific criteria. I renamed a few columns and then later on I tried to do a bit of cleaning so I can work with the data.

I tried to replace percentage signs then convert the data type to a float by doing this:

df = df['IV'].str.rstrip("%").astype(float)
df = df['IV_Rank'].str.rstrip("%").astype(float)/100
df = df['IV PCT'].str.rstrip("%").astype(float)/100

When I run that code I get the error message: KeyError: 'IV'. I got this error for the other columns as well when I tried to run them each independently but I tried copy then pasting the column name as well as trying the old names. I am not too sure what to do but some help would be appreciated

data-cleaning dataframe pandas python
1 Answers

That's because you are overwriting the entire dataframe. This is what I think you are trying to do

df['IV'] = df['IV'].str.rstrip("%").astype(float)
df['IV_Rank'] = df['IV_Rank'].str.rstrip("%").astype(float)/100
df['IV PCT'] = df['IV PCT'].str.rstrip("%").astype(float)/100
Jordan Hyatt0
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