linsolve — linear equation solver
[x0,kerA]=linsolve(A,b [,x0])
a na x ma real matrix (possibly sparse)
a na x 1 vector (same row dimension as A)
a real vector
a ma x k real matrix
linsolve computes all the solutions to A*x+b=0.
x0 is a particular solution (if any) and kerA= nullspace
of A. Any x=x0+kerA*w with arbitrary w satisfies
A*x+b=0.
If compatible x0 is given on entry, x0 is returned. If not
a compatible x0, if any, is returned.