Mathematics

Characteristic Polynomials

The poly function also computes the coefficients of the characteristic polynomial of a matrix.

A = [1.2 3 -0.9; 5 1.75 6; 9 0 1];
poly(A)

ans =
    1.0000   -3.9500   -1.8500  -163.2750

The roots of this polynomial, computed with roots, are the characteristic roots, or eigenvalues, of the matrix A. (Use eig to compute the eigenvalues of a matrix directly.)

Polynomial Roots

Polynomial Evaluation