Filtering and Sorting

Filtering and Sorting

import pandas as pd
df = pd.read_csv('data.csv')

# Filter
active = df[df['is_active'] == True]
adults = df[df['age'].between(18, 65)]
recent = df[df['created_at'] > '2024-01-01']
top    = df[df['score'].gt(90)]  # .gt .lt .ge .le .eq .ne

# Sort
df.sort_values('age')
df.sort_values('age', ascending=False)
df.sort_values(['dept', 'salary'], ascending=[True, False])
df.sort_index()

# Query string (readable alternative)
df.query('age > 25 and score > 90')
df.query('status == "active"')
df.query('name in ["Alice", "Bob"]')

# nlargest / nsmallest
df.nlargest(5, 'score')
df.nsmallest(3, 'age')