How To Count Unique Data In Columns - Pandas For Machine Learning 14

Thank you so much

----> 2 pd.DataFrame(df2['DogName'].unique().head(20))

AttributeError: 'numpy.ndarray' object has no attribute 'head'
Ugh.. any help?

I read the title 'counting unique DNA" and for a moment you had my undivided attention.

I think though, in contemplating the issue, that a heatmap of concentrations of molecules would do the job, while also providing much information at a glance.

My problem solving has got considerably better since I've begun learning to code. Even my math is better, go figure. So thank you.