How to Create Diagonal Matrices in R - Step by Step Examples

How to Create Diagonal Matrices in R ?

Answer

To create diagonal matrices in R, you can use the diag() function. This function can be used in various ways to create matrices with specified diagonal values, either from a single vector or by specifying dimensions and a value.

✐ Examples

1 Creating a Diagonal Matrix from a Vector

In this example,

We start by creating a vector named vec containing the values c(1, 2, 3, 4).
We then use the diag() function with vec as the argument. This function takes the values in vec and places them on the diagonal of a new matrix, with all off-diagonal elements set to zero.
The resulting matrix is stored in a variable named diagonal_matrix.
Finally, we print the value of diagonal_matrix to standard output to see the resulting diagonal matrix.

R Program

vec <- c(1, 2, 3, 4)
diagonal_matrix <- diag(vec)
print(diagonal_matrix)

Output

     [,1] [,2] [,3] [,4]
[1,]    1    0    0    0
[2,]    0    2    0    0
[3,]    0    0    3    0
[4,]    0    0    0    4

2 Creating an Identity Matrix

In this example,

We use the diag() function with a single integer argument 4. This integer specifies the dimensions of the resulting square identity matrix.
The diag() function creates a 4x4 identity matrix, with ones on the diagonal and zeros elsewhere.
The resulting matrix is stored in a variable named identity_matrix.
Finally, we print the value of identity_matrix to standard output to see the identity matrix.

R Program

identity_matrix <- diag(4)
print(identity_matrix)

Output

     [,1] [,2] [,3] [,4]
[1,]    1    0    0    0
[2,]    0    1    0    0
[3,]    0    0    1    0
[4,]    0    0    0    1

3 Creating a Diagonal Matrix with Specified Dimensions and Value

In this example,

We use the diag() function with two arguments: a scalar value 5 and an integer 3. The scalar value specifies the value to be placed on the diagonal, and the integer specifies the dimensions of the resulting square matrix.
The diag() function creates a 3x3 matrix with the value 5 on the diagonal and zeros elsewhere.
The resulting matrix is stored in a variable named custom_diagonal_matrix.
Finally, we print the value of custom_diagonal_matrix to standard output to see the resulting matrix.

R Program

custom_diagonal_matrix <- diag(5, 3)
print(custom_diagonal_matrix)

Output

     [,1] [,2] [,3]
[1,]    5    0    0
[2,]    0    5    0
[3,]    0    0    5

Summary

In this tutorial, we learned How to Create Diagonal Matrices in R language with well detailed examples.

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How to Create Diagonal Matrices in R - Step by Step Examples

How to Create Diagonal Matrices in R ?

Answer

✐ Examples

1 Creating a Diagonal Matrix from a Vector

R Program

Output

2 Creating an Identity Matrix

R Program

Output

3 Creating a Diagonal Matrix with Specified Dimensions and Value

R Program

Output

Summary

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