pracma (version 1.1.0)

poly: Define Polynomial by Roots

Description

Define a polynomial by its roots.

Usage

poly(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, poly(x) is the vector of coefficients of the polynomial whose roots are the elements of x.

See Also

polyval, roots

Examples

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