pandas count occurrences in column
# Basic syntax:
df['column'].value_counts()
# Get normalized counts:
df['column'].value_counts(normalize=True)
# Example usage:
# Make dataframe
import pandas as pd
df = pd.DataFrame(np.array([[1, 2, 3], [4, 5, 6], [7, 5, 9]]),
columns=['a', 'b', 'c'])
print(df)
a b c
0 1 2 3
1 4 5 6
2 7 5 9
df['b'].value_counts() # Returns:
5 2 # 5 appears twice in column 'b'
2 1
df['b'].value_counts(normalize=True) # Returns:
5 0.666667 # 5 accounts for 2/3 of the entries in column 'b'
2 0.333333