Here we are explaining how to write an R program to rotate a given matrix 90-degree clockwise rotation. Here we are using a built-in function matrix() for this conversion. This method helps to creates a matrix from the given set of values. The syntax of this function is,
matrix(data = NA, nrow = 1, ncol = 1, byrow = FALSE,dimnames = NULL)
NA: An optional data vector.
nrow: The desired number of rows.
ncol: The desired number of columns.
byrow: If FALSE (the default) the matrix is filled by columns, otherwise filled by rows.
dimnames: NULL or a list of length 2 giving the row and column names respectively.
Below are the steps used in the R program to rotate a given matrix 90-degree clockwise rotation. In this R program, we directly give the values to built-in functions. And print the function result. Here we used variables Matx for assigning matrix with values 1 to 9. Rotate the matrix by calling like t(apply(Matx, 2, rev)). Here the apply() returns a vector or array obtained by applying a function to an array or matrix. The function t() helps to get the transpose of the given matrix of the data frame.
STEP 1: Assign variable Matx with matrix values
STEP 2: Create a matrix of 1 to 9 elements with 3 rows
STEP 3: Rotate it by calling like t(apply(Matx, 2, rev))
STEP 4: Assign the result into a variable final
STEP 5: print the result matrix final
Matx= matrix(1:9, 3) print("Original matrix:") print(Matx) final = t(apply(Matx, 2, rev)) print("Rotate the matrix 90 degree clockwise:") print(final)
 "Original matrix:" [,1] [,2] [,3] [1,] 1 4 7 [2,] 2 5 8 [3,] 3 6 9  "Rotate the matrix 90 degree clockwise:" [,1] [,2] [,3] [1,] 3 2 1 [2,] 6 5 4 [3,] 9 8 7