In

linear algebra, a

**Toeplitz matrix** is a

square matrix with constant (negative sloping) diagonals, i.e;

In mathematical terms:

These matrices have uses in

computer science because it can be shown that the addition of two Toeplitz matrices can be done in

O(n) time and the

matrix multiplication of two Toeplitz matrices can be done in O(nlogn) time.

The name is after Otto Toeplitz (1881-1940), a German mathematician.