Using "or" in pandas dataframe to search for strings

Question

I would like to do this:

df[(df["Class"] == 'Class1' or  'Class2')]

i.e. find rows with class 1 or 2, but can't find the correct syntax in the documentation.

Answer 1

Better is use isin:

df[df["Class"].isin(['Class1','Class2'])]

Or use | for bitwise or with () because priority precedence of operators with boolean indexing:

df[(df["Class"] == 'Class1') |  (df["Class"] == 'Class2')]

Another solutions with query:

df.query("Class == ['Class1', 'Class2']")

Or:

df.query("Class == 'Class1' |  Class == 'Class2'")
#here working or too
#df = df.query("Class == 'Class1' or  Class == 'Class2'")

Answer 2

These are the options

df[(df["Class"] == 'Class1') |  (df["Class"] =='Class2')]

or

df[df["Class"].isin(['Class1','Class2'])]