Remove all rows that meet regex condition

Question

trying to teach myself pandas.. and playing around with different dtypes

I have a df as follows

df = pd.DataFrame({'ID':[0,2,"bike","cake"], 'Course':['Test','Math','Store','History'] })
print(df)
    ID  Course
0   0   Test
1   2   Math
2   bike    Store
3   cake    History

the dtype of ID is of course an object. What I want to do is remove any rows in the DF if the ID has a string in it.

I thought this would be as simple as..

df.ID.filter(regex='[\w]*')

but this returns everything, is there a sure fire method for dealing with such things?

Answer 1

You can using to_numeric

df[pd.to_numeric(df.ID,errors='coerce').notnull()]
Out[450]: 
  Course ID
0   Test  0
1   Math  2