Yes, there is a way in Julia to reshape and fill the elements in row major ways. In this article, we will explore three different options to achieve this.
Option 1: Using the reshape function
The reshape function in Julia allows us to reshape an array while preserving the order of the elements. To fill the elements in row major order, we can use the colon operator to create a range of values and reshape it accordingly.
# Input array
input_array = [1, 2, 3, 4, 5, 6, 7, 8, 9]
# Reshape the array in row major order
reshaped_array = reshape(input_array, (3, 3))'
# Output
println(reshaped_array)
The above code reshapes the input array into a 3×3 matrix and transposes it to achieve row major order. The output will be:
[1 4 7]
[2 5 8]
[3 6 9]
Option 2: Using the reshape! function
If you want to reshape the array in-place, you can use the reshape! function. This function modifies the input array directly, without creating a new array.
# Input array
input_array = [1, 2, 3, 4, 5, 6, 7, 8, 9]
# Reshape the array in row major order
reshape!(input_array, (3, 3))'
# Output
println(input_array)
The above code reshapes the input array into a 3×3 matrix in row major order. The output will be the modified input array:
[1 4 7]
[2 5 8]
[3 6 9]
Option 3: Using the permutedims function
Another way to achieve row major order is by using the permutedims function. This function permutes the dimensions of an array according to the specified permutation order.
# Input array
input_array = [1, 2, 3, 4, 5, 6, 7, 8, 9]
# Reshape the array in row major order
reshaped_array = permutedims(reshape(input_array, (3, 3)), (2, 1))
# Output
println(reshaped_array)
The above code reshapes the input array into a 3×3 matrix and permutes the dimensions to achieve row major order. The output will be:
[1 4 7]
[2 5 8]
[3 6 9]
Among the three options, the best choice depends on your specific requirements. If you want to preserve the original array and create a new reshaped array, option 1 using the reshape function is a good choice. If you prefer to modify the input array directly, option 2 using the reshape! function is more suitable. Option 3 using the permutedims function is useful if you need to permute the dimensions of the array in addition to reshaping it.
