Navigation

Operators and Keywords

Function List:

• » Octave core
• » by package
• » alphabetical

C++ API

: compan (c)

Compute the companion matrix corresponding to polynomial coefficient vector c.

The companion matrix is

     _                                                        _
    | -c(2)/c(1)   -c(3)/c(1)  …  -c(N)/c(1)  -c(N+1)/c(1)  |
    |      1            0      …       0             0      |
    |      0            1      …       0             0      |
A = |      .            .      .         .             .      |
    |      .            .       .        .             .      |
    |      .            .        .       .             .      |
    |_      0            0      …       1             0     _|

The eigenvalues of the companion matrix are equal to the roots of the polynomial.

See also: roots, poly, eig.

Package: octave