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Python Pandas - Get unique values from a column
To get unique values from a column in a DataFrame, use the unique(). To count the unique values from a column in a DataFrame, use the nunique().
At first, import the required library −
import pandas as pd;
Create a DataFrame with 3 columns. We have duplicate values as well −
dataFrame = pd.DataFrame(
{
"Car": ['BMW', 'Audi', 'BMW', 'Lexus', 'Tesla', 'Lexus', 'Mustang'],"Place": ['Delhi','Bangalore','Hyderabad','Chandigarh','Pune', 'Mumbai', 'Jaipur'],"Units": [100, 150, 50, 110, 90, 120, 80]
}
)Get unique values with the count −
print"\nUnique values from a column ...\n",dataFrame['Car'].unique() print"\nCount unique values from a column ...\n",dataFrame['Car'].nunique()
Example
Following is the code −
import pandas as pd;
# create a DataFrame
dataFrame = pd.DataFrame(
{
"Car": ['BMW', 'Audi', 'BMW', 'Lexus', 'Tesla', 'Lexus', 'Mustang'],"Place": ['Delhi','Bangalore','Hyderabad','Chandigarh','Pune', 'Mumbai', 'Jaipur'],"Units": [100, 150, 50, 110, 90, 120, 80]
}
)
print"DataFrame ...\n",dataFrame
# get unique values from a column
print"\nUnique values from a column ...\n",dataFrame['Car'].unique()
print"\nCount unique values from a column ...\n",dataFrame['Car'].nunique()Output
This will produce the following output −
DataFrame ... Car Place Units 0 BMW Delhi 100 1 Audi Bangalore 150 2 BMW Hyderabad 50 3 Lexus Chandigarh 110 4 Tesla Pune 90 5 Lexus Mumbai 120 6 Mustang Jaipur 80 Unique values from a column ... ['BMW' 'Audi' 'Lexus' 'Tesla' 'Mustang'] Count unique values from a column ... 5
Updated on: 16-Sep-2021
11K+ Views
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