Python Pandas Dataframe - Largest and Smallest Rows

Here is an example on how identify largest or smallest n rows.
Source Data : Census data for state of California.

Use Case : 
Read Population data for state of California from "censusdata.ire.org".
Get 3 Counties with highest population.
Get 3 Counties with lowest population.

Syntax : 

  DataFrame.nlargest()
  DataFrame.nsmallest()

Main Parameters :

• Number of Items to retrieve
• Columns to sort on
• Rows to keep in case of duplicates ( keep=first or keep=last )

Sample Code

Read Source Data and select subset of columns.

County name and Population selected.

import pandas as pd

df = pd.read_csv("http://censusdata.ire.org/06/all_050_in_06.P1.csv")

df = df[["NAME","POP100"]]

df

Select Top 3 counties with highest population

df.nlargest(3,"POP100")

Select 3 counties with lowest population
df.nsmallest(3,"POP100")