Unique value on columns – pandas


Today is a short example on cases that have longer columns with spaces.

For example. I have a dataframe that has the following columns:

I have read in some sources that you can use the construction wine_new.[column name].unique() to filter the values.

If you have a one word column, it will work, but if the column is listed as multiple words, you can not use a construct like wine_new.’Page ID’.unique() because it will give a syntax error.

Good, so you try to rename it. why Page ID and not pageid? Ok, that should be easy

wine_new = wine_new.rename(columns={"Page ID": "pageid"}, errors="raise")

And it now looks “better”.

But if you need to keep the column name, you can just as easily use wine_new[‘Page ID’].unique() (If you want to count the number of unique values you can also use wine_new[‘Page ID’].nunique())

There are multiple resources on this topic but the approach is not explained using both of the versions on the majority of them.