kernel

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 (null space) of A, and size(W,2) is the nullity 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