How to change a dataframe column to lower case

How to change a dataframe column to lower case - Printable Version

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How to change a dataframe column to lower case - zhujp98 - Oct-29-2019

# Import pandas library 
import pandas as pd 
  
# initialize list of lists 
data = [['tom', 10], ['nick', 15], ['juli', 14]] 
  
# Create the pandas DataFrame 
df = pd.DataFrame(data, columns = ['Name', 'AGE'])

I want to change on of the field AGE to age, keep Name unchanged .
How Can I do it?
Thanks,
Jeff

RE: How to change a dataframe column to lower case - newbieAuggie2019 - Oct-29-2019

(Oct-29-2019, 03:42 PM)zhujp98 Wrote:
# Import pandas library 
import pandas as pd 
  
# initialize list of lists 
data = [['tom', 10], ['nick', 15], ['juli', 14]] 
  
# Create the pandas DataFrame 
df = pd.DataFrame(data, columns = ['Name', 'AGE']) 
I want to change on of the field AGE to age, keep Name unchanged .
How Can I do it?
Thanks,
Jeff

Hi!

If I understand correctly, it is you who is creating the columns and giving the names of the columns with the line:

df = pd.DataFrame(data, columns = ['Name', 'AGE'])

so have you tried changing that line to:

df = pd.DataFrame(data, columns = ['Name', 'age'])

All the best,

RE: How to change a dataframe column to lower case - zhujp98 - Oct-29-2019

Thanks,
I want to use program to do that.

The short code is just a simple example. I actually have a very large table with 50 columns. The dataframe is created from a .csv file. I want to change one of columns to lower case.
Thanks,
Jeff

RE: How to change a dataframe column to lower case - newbieAuggie2019 - Oct-29-2019

(Oct-29-2019, 04:11 PM)zhujp98 Wrote: I want to change one of columns to lower case.

Hi again!

Then maybe you could use something like:

df['AGE'].str.lower()

and if it is for all the columns, you could use something like:

data.columns = [x.lower() for x in data.columns]

I have based my answer on these:

https://stackoverflow.com/questions/22245171/how-to-lowercase-a-pandas-dataframe-string-column-if-it-has-missing-values

https://stackoverflow.com/questions/19726029/how-can-i-make-pandas-dataframe-column-headers-all-lowercase

All the best,

RE: How to change a dataframe column to lower case - ichabod801 - Oct-29-2019

If you are trying to change the name of the column, rather than the values of the column, you can use rename:

df.rename(columns = {'AGE': 'age'}, inplace = True)

RE: How to change a dataframe column to lower case - zhujp98 - Oct-29-2019

thanks!