python-pandasHow to count unique values
import pandas as pd
df = pd.DataFrame({
'type': ['A', 'A', 'A', 'B', 'B', 'C'],
'age': [1, 3, 6, 3, 4, 1]
})
uniq_count = df.type.unique().sizectrl + cimport pandas as pdload Pandas module | pd.DataFramecreates Pandas DataFrame object |
df.typeaddress | .unique()will return unique values for a specified column |
.sizereturn length of a given array | uniq_countwill contain unique values size |
Usage example
import pandas as pd
df = pd.DataFrame({
'type': ['A', 'A', 'A', 'B', 'B', 'C'],
'age': [1, 3, 6, 3, 4, 1]
})
print(df.type.unique().size)output
3
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