Golang Program To Rotate Matrix Elements

In this article, we will write a go language program to rotate given matrix element.

Rotate A Matrix Using An External Function

The following code illustrates rotating a matrix anticlockwise by 90 degrees any number of times.

Algorithm

Step 1 ? Import the fmt package.

Step 2 ? Create a function to rotate the array elements. This function takes the array to be rotated as argument.

Step 3 ? Also pass the number of times the array is to be shifted as argument. Further, initialize an empty matrix to hold the final result.

Step 4 ? In the function use two for loops to intend over the matrix and update the new matrix elements at a different row each time. return the final matrix thus obtained.

Step 5 ? Start the main() function. Here, create a 3 X 3 matrix and print it on the screen.

Step 6 ? Call the rotateMatrix() function by passing respective parameters and store the result obtained in a separate variable.

Step 7 ? Print the final result on the screen using for loops and fmt.Println() function.

Example

package main import "fmt" // function to rotate matrix func rotateMatrix(X [][]int, n int) [3][3]int { var temp [3][3]int for i := 0; i < n; i++ { for j := 0; j < n; j++ { temp[n-j-1][i] = X[i][j] } } return temp } func main() { mat := [][]int{ {10, 1, 2}, {4, 5, 6}, {8, 9, 10}, } fmt.Println("The given matrix is: \n") for i := 0; i < 3; i++ { for j := 0; j < 3; j++ { fmt.Print(mat[i][j], "\t") } fmt.Println() } fmt.Println() var n int = 3 result := rotateMatrix(mat, n) fmt.Println("The matrix obtained after rotating the above matrix to", n, "Positions is:") fmt.Println() for i := 0; i < 3; i++ { for j := 0; j < 3; j++ { fmt.Print(result[i][j], "\t") } fmt.Println() } } 

Output

The given matrix is: 10	1	2 4	5	6 8	9	10 The matrix obtained after rotating the above matrix to 3 Positions is: 2	6	10 1	5	9 10	4	8 

Rotate Elements Of The Array In Clockwise Direction N Times

In this example, we will write a go language program to shift elements of the array to a clockwise direction any number of times.

Algorithm

Step 1 ? Import the fmt package.

Step 2 ? Start the main() function. Here, create a 3 X 3 matrix and print it on the screen.

Step 3 ? Print the final result on the screen using for loops and fmt.Println() function.

Step 4 ? Use for loops to intend over the array and shift the positions of the array to a clockwise direction respectively.

Step 5 ? Now, print the array on the screen using fmt.Println() function.

Example

package main import "fmt" // calling main() func main() { // initializing a 3 X 3 matrix mat := [3][3]int{ {1, 3, 2}, {4, 5, 6}, {8, 9, 10}, } fmt.Println("The given matrix is: \n") for i := 0; i < 3; i++ { for j := 0; j < 3; j++ { fmt.Print(mat[i][j], "\t") } fmt.Println() } var N int = 3 fmt.Println() fmt.Println("The matrix obtained after rotating the above matrix to", N, "Positions clock wise is:") fmt.Println() for i := N - 1; i >= 0; i-- { for j := N - 1; j >= 0; j-- { fmt.Print(mat[i][j], "\t") } fmt.Println() } } 

Output

The given matrix is: 1	3	2 4	5	6 8	9	10 The matrix obtained after rotating the above matrix to 3 Positions clock wise is: 10	9	8 6	5	4 2	3	1 

Rotate Elements Of An Array By 180 Degrees

In this example, we will write a go program to rotate elements of a matrix by 180 degrees

Algorithm

Step 1 ? Import the fmt package.

Step 2 ? Create functions naming reverseColumns(), transpose() and printMatrix() to reverse columns of the matrix, find its transpose and print the elements respectively.

Step 3 ? Also pass the matrix as an argument to the function.

Step 4 ? In these functions, we are using for loops to carry out the respective operation.

Step 5 ? Start the main() function. Here, create a 3 X 3 matrix and print it on the screen.

Step 6 ? Call the rotate180() and printMatrix() function by passing the array as argument.

Example

package main import "fmt" func reverseColumns(arr [][]int) { var c int = 3 for i := 0; i < 3; i++ { for j, k := 0, c-1; j < k; j, k = j+1, k-1 { t := arr[j][i] arr[j][i] = arr[k][i] arr[k][i] = t } } } func transpose(arr [][]int) { for i := 0; i < 3; i++ { for j := i; j < 3; j++ { t := arr[i][j] arr[i][j] = arr[j][i] arr[j][i] = t } } } func printMatrix(arr [][]int) { for i := 0; i < 3; i++ { for j := 0; j < 3; j++ { fmt.Print(arr[i][j], "\t") } fmt.Println() } } func rotate180(arr [][]int) { transpose(arr) reverseColumns(arr) transpose(arr) reverseColumns(arr) } // calling main() func main() { // initializing a 3 X 3 matrix mat := [][]int{ {1, 3, 2}, {4, 5, 6}, {8, 9, 10}, } // printing matrix fmt.Println("The given matrix is: \n") for i := 0; i < 3; i++ { for j := 0; j < 3; j++ { fmt.Print(mat[i][j], "\t") } fmt.Println() } fmt.Println() fmt.Println("The matrix obtained after rotating the above matrix to", 3, "Positions clock wise is:") fmt.Println() rotate180(mat) printMatrix(mat) } 

Output

The given matrix is: 1	3	2 4	5	6 8	9	10 The matrix obtained after rotating the above matrix to 3 Positions clock wise is: 10	9	8 6	5	4 2	3	1 

Conclusion

In this article, we have successfully executed a golang code to rotate array elements along with examples. We have seen three different examples here, in the first one; we rotated the matrix clockwise direction in 90 degreess. In the second example, we rotated the matrix N number of times and in the third example, we rotated the matrix 180 degrees.