pracma (version 0.4-0)

polydef: Define Polynomial by Roots

Description

Define a polynomial by its roots.

Usage

polydef(x)

Arguments

x

vector or square matrix

Value

• Vector representing a polynomial.

Details

Computes the characteristic polynomial of an (n x n)-Matrix.

If x is a vector, polydef(x) is the vector of coefficients of the polynomial whose roots are the elements of x.

See Also

polyval, roots

Examples

polydef(c(1, -1, 1i, -1i))  # Solves x^4 -1 = 0
  # Wilkinson's example:
  roots(polydef(1:20))