How to find the unique values of a column in a DataFrame?

by Amrita Mitra | Nov 12, 2022 | Machine Learning Using Python, Python Pandas

pandas Series that contains the values from the species column. Then, we are calling the Series.nunique() function to get the total number of unique values in the Series.

On the other hand, pandas.unique(df[“species”]) gives us the unique values contained in the species column of the DataFrame.

The output of the above program will be:

   sepal_length  sepal_width  petal_length  petal_width species
0           5.1          3.5           1.4          0.2  setosa
1           4.9          3.0           1.4          0.2  setosa
2           4.7          3.2           1.3          0.2  setosa
3           4.6          3.1           1.5          0.2  setosa
4           5.0          3.6           1.4          0.2  setosa
Total number of unique values:  3
The unique values:  ['setosa' 'versicolor' 'virginica']

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