How to Combine Matrices by Rows in R - Step by Step Examples

How to Combine Matrices by Rows in R ?

Answer

To combine matrices by rows in R, you can use the rbind() function. This function takes two or more matrices as arguments and combines them by rows, resulting in a new matrix where the rows of the input matrices are concatenated one after the other.

How to Combine Matrices by Rows in r language

✐ Examples

1 Combining Two Matrices by Rows

In this example,

  1. We create a matrix named matrix1 with the values from 1 to 6 arranged in 2 rows and 3 columns using the matrix() function. The matrix() function takes a vector of values and the arguments nrow and ncol to specify the number of rows and columns respectively.
  2. We then create another matrix named matrix2 with the values from 7 to 12 arranged in 2 rows and 3 columns using the matrix() function.
  3. We use the rbind() function to combine matrix1 and matrix2 by rows. This function concatenates the rows of matrix1 and matrix2 one after the other, resulting in a new matrix named combined_matrix.
  4. The rbind() function returns a new matrix with the combined rows of the input matrices.
  5. Finally, we print the value of combined_matrix to standard output to see the combined result.

R Program

matrix1 <- matrix(1:6, nrow = 2, ncol = 3)
matrix2 <- matrix(7:12, nrow = 2, ncol = 3)
combined_matrix <- rbind(matrix1, matrix2)
print(combined_matrix)

Output

     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6
[3,]    7    9   11
[4,]    8   10   12

2 Combining Three Matrices by Rows

In this example,

  1. We create a matrix named matrix1 with the values from 1 to 4 arranged in 2 rows and 2 columns using the matrix() function. The matrix() function takes a vector of values and the arguments nrow and ncol to specify the number of rows and columns respectively.
  2. We then create another matrix named matrix2 with the values from 5 to 8 arranged in 2 rows and 2 columns using the matrix() function.
  3. Next, we create a third matrix named matrix3 with the values from 9 to 12 arranged in 2 rows and 2 columns using the matrix() function.
  4. We use the rbind() function to combine matrix1, matrix2, and matrix3 by rows. This function concatenates the rows of the three matrices one after the other, resulting in a new matrix named combined_matrix.
  5. The rbind() function returns a new matrix with the combined rows of the input matrices.
  6. Finally, we print the value of combined_matrix to standard output to see the combined result.

R Program

matrix1 <- matrix(1:4, nrow = 2, ncol = 2)
matrix2 <- matrix(5:8, nrow = 2, ncol = 2)
matrix3 <- matrix(9:12, nrow = 2, ncol = 2)
combined_matrix <- rbind(matrix1, matrix2, matrix3)
print(combined_matrix)

Output

     [,1] [,2]
[1,]    1    3
[2,]    2    4
[3,]    5    7
[4,]    6    8
[5,]    9   11
[6,]   10   12

3 Combining Matrices of Different Sizes by Rows

In this example,

  1. We create a matrix named matrix1 with the values from 1 to 6 arranged in 2 rows and 3 columns using the matrix() function. The matrix() function takes a vector of values and the arguments nrow and ncol to specify the number of rows and columns respectively.
  2. We then create another matrix named matrix2 with the values from 7 to 8 arranged in 1 row and 3 columns using the matrix() function.
  3. We use the rbind() function to combine matrix1 and matrix2 by rows. This function concatenates the rows of matrix1 and matrix2 one after the other, resulting in a new matrix named combined_matrix.
  4. The rbind() function returns a new matrix with the combined rows of the input matrices.
  5. Finally, we print the value of combined_matrix to standard output to see the combined result.

R Program

matrix1 <- matrix(1:6, nrow = 2, ncol = 3)
matrix2 <- matrix(7:9, nrow = 1, ncol = 3)
combined_matrix <- rbind(matrix1, matrix2)
print(combined_matrix)

Output

     [,1] [,2] [,3]
[1,]    1    3    5
[2,]    2    4    6
[3,]    7    8    9

Summary

In this tutorial, we learned How to Combine Matrices by Rows in R language with well detailed examples.


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