kernel

kernel, nullspace

Calling Sequence

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

Arguments

: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 column compression, kernel, nullspace
• fullrf full rank factorization
• fullrfk full rank factorization of A^k
• linsolve linear equation solver