how do you convert data frame column values to integer

Question

I need to convert data frame column to int.

df['Slot'].unique()

displays this:

array(['1', '2', '3', '4', 1, 3, 5], dtype=object)

some values have '' around it some dont.

I tried to convert the data type to int as below:

df['Slot']=df['Slot'].astype('Int64')

I get this error:

TypeError: cannot safely cast non-equivalent object to int64

Any ideas how to convert to int?

Answer 1

You should first convert to numeric, then cast to Int64:

df['Slot'] = pd.to_numeric(df['Slot']).astype('Int64')

After casting the type:

df.dtypes

Slot    Int64
dtype: object

As noted in comments, if you use numpy's int64 type this works from scratch:

df['Slot'].astype('int64')