The title words remind of an unrelated fact, Gershgorin Disks:
The eigenvalues of any N x N matrix, A,
are contained in the union of N discs in the complex plane.
The center of the i_th disc is the i_th diagonal element of A.
The radius of the i_th disc is the absolute values
of the off-diagonal elements in the i_th row.
It's rather remarkable, unexpected, and perhaps shocking, when you first hear it. There does not seem to be enough information to make it true. But it is.
It's rather remarkable, unexpected, and perhaps shocking, when you first hear it. There does not seem to be enough information to make it true. But it is.
I used it in a real project to cancel noise.