Singular value decomposition

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is any m by n matrix, square or rectangular. Its rank is r. We will diagonalize this A, but not by Failed to parse (syntax error): {\displaystyle X^{−1}AX} . The eigenvectors in have three big problems: They are usually not orthogonal, there are not always enough eigenvectors, and = Failed to parse (syntax error): {\displaystyle λx} requires to be a square matrix. The singular vectors of solve all those problems in a perfect way.

Task
Singular value decomposition
You are encouraged to solve this task according to the task description, using any language you may know.

The Singular Value Decomposition (SVD)

According to the web page above, for any rectangular matrix , we can decomposite it as Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle A=UΣV^T}

Task Description

Firstly, input two numbers "m" and "n".

Then, input a square/rectangular matrix .

Finally, output Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle U,Σ,V} with respect to .

Example

Sample Input

2 2
3 0
4 5

From the input above we can know that is a 2 by 2 matrix.

Sample Output

   
0.31622776601683794 -0.9486832980505138
0.9486832980505138 0.31622776601683794

6.708203932499369 0
0 2.23606797749979

0.7071067811865475 -0.7071067811865475
0.7071067811865475 0.7071067811865475

The output may vary depending your choice of the data types.


Julia

Julia has an svd() function as part of its built-in LinearAlgebra package.

julia> using LinearAlgebra

julia> function testsvd()
           rows, cols = [parse(Int, s) for s in split(readline())]
           arr = zeros(rows, cols)
           for row in 1:rows
               arr[row, :] .= [tryparse(Float64, s) for s in split(readline())]
           end
           display(svd(arr))
       end
testsvd (generic function with 1 method)

julia> testsvd()
2 2
3 0
4.5
SVD{Float64, Float64, Matrix{Float64}, Vector{Float64}}
U factor:
2×2 Matrix{Float64}:
 -0.346946  -0.937885
 -0.937885   0.346946
singular values:
2-element Vector{Float64}:
 6.74492216626026
 2.0015056760076915
Vt factor:
2×2 Matrix{Float64}:
 -0.780042  -0.625727
 -0.625727   0.780042