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Orthogonal Basis for Null Space of a Matrix
Syntax y = null(x)
See Also null , svd

Description
Computes an orthogonal basis for the null space of the integer, real, double-precision or complex matrix x. Thus x * y is numerically near zero.

If x is an integer matrix, y is double-precision. Otherwise y has the same type as x. The number of rows in y is equal to the number of columns in x and the number of columns in y is equal to the dimension of the null space of x. Each of the columns of the matrix y has norm one and the columns are orthogonal; i.e.;
     I = conj(y)' * y
where I is the identity matrix with the same number of columns as y.

Example
If you enter
     x = { [1 , 1 , 1], [1 , 2 , 3] }
     y = null(x)
     y
O-Matrix will reply
     {
     0.408248
     -0.816497
     0.408248
     }
Continuing with
     y' * y
results in
     1
and
     x * y
results in
     {
     0
     0
     }