How to get Row Names in a Matrix in R - Step by Step Examples

How to get Row Names in a Matrix in R ?

Answer

To get the row names of a matrix in R, you can use the rownames() function. This function retrieves the row names as a vector.

✐ Examples

1 Get Row Names of a 2x2 Matrix

In this example,

First, we create a 2x2 matrix named matrix1 using the matrix() function with a vector of values c(1, 2, 3, 4) and specify the number of rows as 2.
We assign row names c('Row1', 'Row2') to the matrix using the rownames() function.
To get the row names, we use the rownames() function on matrix1 and store the result in a variable called rowNames1.
Finally, we use the print() function to display the row names stored in rowNames1.

R Program

matrix1 <- matrix(c(1, 2, 3, 4), nrow = 2)
rownames(matrix1) <- c('Row1', 'Row2')
rowNames1 <- rownames(matrix1)
print(rowNames1)

Output

[1] "Row1" "Row2"

2 Get Row Names of a 3x3 Matrix

In this example,

We first create a 3x3 matrix named matrix2 using the matrix() function with a vector of values c(1, 2, 3, 4, 5, 6, 7, 8, 9) and specify the number of rows as 3.
We assign row names c('A', 'B', 'C') to the matrix using the rownames() function.
To get the row names, we use the rownames() function on matrix2 and store the result in a variable called rowNames2.
Finally, we use the print() function to display the row names stored in rowNames2.

R Program

matrix2 <- matrix(c(1, 2, 3, 4, 5, 6, 7, 8, 9), nrow = 3)
rownames(matrix2) <- c('A', 'B', 'C')
rowNames2 <- rownames(matrix2)
print(rowNames2)

Output

[1] "A" "B" "C"

3 Get Row Names of a 4x2 Matrix

In this example,

First, we create a 4x2 matrix named matrix3 using the matrix() function with a vector of values c(10, 20, 30, 40, 50, 60, 70, 80) and specify the number of rows as 4.
We assign row names c('R1', 'R2', 'R3', 'R4') to the matrix using the rownames() function.
To get the row names, we use the rownames() function on matrix3 and store the result in a variable called rowNames3.
Finally, we use the print() function to display the row names stored in rowNames3.

R Program

matrix3 <- matrix(c(10, 20, 30, 40, 50, 60, 70, 80), nrow = 4)
rownames(matrix3) <- c('R1', 'R2', 'R3', 'R4')
rowNames3 <- rownames(matrix3)
print(rowNames3)

Output

[1] "R1" "R2" "R3" "R4"

Summary

In this tutorial, we learned How to get Row Names in a Matrix in R language with well detailed examples.

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How to get Row Names in a Matrix in R - Step by Step Examples

How to get Row Names in a Matrix in R ?

Answer

✐ Examples

1 Get Row Names of a 2x2 Matrix

R Program

Output

2 Get Row Names of a 3x3 Matrix

R Program

Output

3 Get Row Names of a 4x2 Matrix

R Program

Output

Summary

More R Matrices Tutorials