random sampling in pandas python – random n rows

Selection of random n rows in pandas python is carried out using sample() function. So this is nothing but simple random sampling in pandas.

Let’s see how to

• Select random n rows in pandas python.
• Select random n% of rows in pandas dataframe – python

With an example for each. First let’s create a dataframe.

import pandas as pd
import numpy as np

#Create a DataFrame
df1 = {
     'Name':['George','Andrea','micheal','maggie','Ravi','Xien','Jalpa'],
   'Mathematics_score':[62,47,55,74,32,77,86]}

df1 = pd.DataFrame(df1,columns=['Name','Mathematics_score'])
print(df1)

df1 will be

Select random n rows in a pandas python (random sampling in pandas):

Random n rows of a dataframe is selected using sample function and with argument  n as number of rows  as shown below.

''' Random sampling - Random n rows '''
df1_elements = df1.sample(n=4)
print(df1_elements)

so the resultant dataframe will select 4 random rows from dataframe df1

Select random n% rows in a pandas dataframe python 

Random n% of rows in a dataframe is selected using sample function and with argument frac as percentage of rows as shown below.

''' Random sampling - Random n% rows '''
df1_percent = df1.sample(frac=0.7)
print(df1_percent)

so the resultant dataframe will select 70% of rows randomly from dataframe df1.