kernel

Scilab Function
Last update : April 1993

kernel - kernel, nullspace

### Calling Sequence

  `W=kernel(A [,tol,[,flag])`

### Parameters

- `A`: full real or complex matrix or real sparse matrix
- `flag`: character string `'svd'` (default) or `'qr'`
- `tol`: real number
- `W`: full column rank matrix

### Description

`W=kernel(A)` returns the kernel (nullspace) of `A`. If A has full column rank then an empty matrix [] is returned.

`flag` and `tol` are optional parameters: `flag = 'qr'` or `'svd'` (default is `'svd'`).

`tol` = tolerance parameter (of order `%eps` as default value).

### Examples

    A=rand(3,1)*rand(1,3);
    A*kernel(A)
    A=sparse(A);
    clean(A*kernel(A))

### See Also

`colcomp`, `fullrf`, `fullrfk`, `linsolve`,

### Author

F.D.;