Null {MASS} | R Documentation |
Given a matrix, M
, find a matrix N
giving a basis for the
null space. That is t(N) %*% M
is the zero and N
has the maximum number of linearly
independent columns.
Null(M)
M |
Input matrix. A vector is coerced to a 1-column matrix. |
The matrix N
with the basis for the null space, or an empty
vector if the matrix M
is square and of maximal rank.
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer.
# The function is currently defined as function(M) { tmp <- qr(M) set <- if(tmp$rank == 0) 1:ncol(M) else - (1:tmp$rank) qr.Q(tmp, complete = TRUE)[, set, drop = FALSE] }