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How to divide two columns element-wise in a pandas dataframe?

Given a pandas dataframe, we have to divide two columns element-wise.
Submitted by Pranit Sharma, on November 14, 2022

Pandas is a special tool that allows us to perform complex manipulations of data effectively and efficiently. Inside pandas, we mostly deal with a dataset in the form of DataFrame. DataFrames are 2-dimensional data structures in pandas. DataFrames consist of rows, columns, and data.

Columns are the different fields that contain their particular values when we create a DataFrame. We can perform certain operations on both row & column values.

Problem statement

We are given a DataFrame with two columns A and B, we need to divide column A with column B, values by value.

Dividing two columns element-wise

For this purpose, we will simply define an expression of df['A']/df['B'] and store the result in a new column.

This expression runs in a way so that it takes the first value of column A at a time and divides it by the first value of column B and so on and stores the corresponding value of the new column.

Let us understand with the help of an example,

Python program to divide two columns element-wise in a pandas dataframe

# Importing pandas package
import pandas as pd

# Importing numpy package
import numpy as np

# Creating a Dictionary
d = {
    'A':[12,18,90,24,50],
    'B':[6,9,10,3,25]
}

# Creating DataFrame
df = pd.DataFrame(d)

# Display dataframe
print('Original DataFrame:\n',df,'\n')

# Creating new column
df['New'] = df['A']/df['B']

# Display new DataFrame
print("New DataFrame:\n",df,"\n")

Output

The output of the above program is:

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