sva

Scilab Function
Last update : April 1993

sva - singular value approximation

### Calling Sequence

  `[U,s,V]=sva(A,k)`
  `[U,s,V]=sva(A,tol)`

### Parameters

- `A`: real or complex matrix
- `k`: integer
- `tol`: nonnegative real number

### Description

Singular value approximation.

`[U,S,V]=sva(A,k)` with `k` an integer >=1, returns `U,S` and `V` such that `B=U*S*V'` is the best L2 approximation of `A` with rank(`B`)=`k`.

`[U,S,V]=sva(A,tol)` with `tol` a real number, returns `U,S` and `V` such that `B=U*S*V'` such that L2-norm of `A-B` is at most `tol`.

### Examples

    A=rand(5,4)*rand(4,5);
    [U,s,V]=sva(A,2);
    B=U*s*V';
    svd(A)
    svd(B)
    clean(svd(A-B))

### See Also

`svd`,