Course

Additional

Find the Statistical Mode Write to a File Format Decimal Places

Data Frames

Convert a List to a Dataframe Create an Empty Dataframe Combine Two Dataframe into One Change Column Name of a Dataframe Extract Columns From a Dataframe Drop Columns in a Dataframe Reorder Columns in a Dataframe Split Dataframe Merge Multiple Dataframes Delete Rows From Dataframe Make a List of Dataframes

Introduction

"Hello World" Program Add Two Vectors Find Sum, Mean and Product of Vector in R Programming Take Input From User Generate Random Number from Standard Distributions Sample from a Population Find Minimum and Maximum Sort a Vector

Strings

Concatenate Two Strings Find the Length of a String Check if Characters are Present in a String Extract n Characters From a String Replace Characters in a String Compare two Strings Convert Factors to Characters Trim Leading and Trailing Whitespaces

Vectors

Concatenate a Vector of Strings Check if a Vector Contains the Given Element Count the Number of Elements in a Vector Find Index of an Element in a Vector Access Values in a Vector Add Leading Zeros to Vector

Decision and Loops

Find the Factorial of a Number R Multiplication Table Check Prime Number check Armstrong Number Print the Fibonacci Sequence Check for Leap Year Check if a Number is Odd or Even in R Programming Check if a Number is Positive, Negative or Zero Find the Sum of Natural Numbers

Functions

Convert Decimal into Binary using Recursion in R Find the Factorial of a Number Using Recursion Find the Factors of a Number Fibonacci Sequence Using Recursion in R Find H.C.F. or G.C.D.Find L.C.M.Make a Simple Calculator Sum of Natural Numbers Using Recursion

R Program to Find Index of an Element in a Vector

Example 1: Find Index Value of R Vector Element Using match()


              
# create two strings
vowel_letters <- c("a", "e", "i", "o", "u")

# find index value of "i"
match("i", vowel_letters) # 3

# find index value of "u"
match("u", vowel_letters) # 5

Output


              
[1] 3
[1] 5

In the above example, we have used the match() function to find the index of an element in the vector named vowel_letters.

Here,

"i" is present in vowel_letters at the 3rd index, so the method returns 3
"u" is present in vowel_letters at the 5th index, so the method returns 5

Example 2: Find Index Value of R Vector Element Using which()


              
# create two strings
languages <- c("R", "Swift", "Java", "Python")

# find index value of "Swift" using which()
which(languages == "Swift") # 2

# find index value of "Python" using which()
which(languages == "Python") # 4

Output


              
[1] 2
[2] 4

Here, we have used the which() function to find the index value of an element.

Since,

"Swift" is present in languages at the 2nd index, so the method returns 2
"Python" is present in languages at the 4th index, so the method returns 4