Find number of months between two dates in R

In this article, we will discuss how to Find the number of months between two dates in the R programming language. 

Example:

Input: Date_1 = 2020/02/21

  Date_2 = 2020/03/21

Output: 1

Explanation: In Date_1 and Date_2 have only one difference in month.

Here we will use seq() function to get the result. This function is used to create a sequence of elements in a Vector. It takes the length and difference between values as optional argument.

Syntax: length(seq(from=date_1, to=date_2, by=’month’)) -1 

Where: seq is function generates a sequence of numbers, from is starting date, to is ending date.

Example 1: In the below example, we are storing two dates in two different variables and by using length(seq(from=date_1, to=date_2, by=’month’)) we are finding a number of months between these two dates.

R

# creating date_1 variable and storing date in it.
date_1<-as.Date("2020-08-10")

# creating date_2 variable and storing date in it.
date_2<-as.Date("2020-10-10")

# Here first date will  start from 2020-08-10 and
# end by 2020-10-10.Here increment is done by month.
# This three dates  will be generated as we used
# seq and this dates will be stored in a.
a = seq(from = date_1, to = date_2, by = 'month'))

# Here we are finding length of a and we are subtracting
# 1 because we dont need to include current month.
length(a)-1

Output:

2

Example 2: Checking with different dates.

R

# creating date_1 variable and storing date in it.
date_1<-as.Date("2020-01-23")

# creating date_2 variable and storing date in it.
date_2<-as.Date("2020-9-25")

# Here first date will  start from 2020-01-23
# and end by 2020-9-25.Here increment is done
# by month.This three dates  will be generated
# as we used seq and this dates will be stored in a.
a=seq(from = date_1, to = date_2, by = 'month'))

# Here we are finding length of a and we are
# subtracting 1 because we dont need to include
# current month.
length(a)-1

Output:

8