| polyroot {base} | R Documentation |
Find Zeros of a Real or Complex Polynomial
Description
Find zeros of a real or complex polynomial.
Usage
polyroot(z)
Arguments
z |
the vector of polynomial coefficients in decreasing order. |
Details
A polynomial of degree n - 1,
p(x) = z_1 + z_2 x + \cdots + z_n x^{n-1}
is given by its coefficient vector z[1:n].
polyroot returns the n-1 complex zeros of p(x)
using the Jenkins-Traub algorithm.
Value
A complex vector of length n - 1, where n is
length(z).
References
Jenkins and Traub (1972) TOMS Algorithm 419. Comm. ACM, 15, 97–99.
See Also
uniroot for numerical root finding of arbitrary
functions;
complex and the zero example in the demos
directory.
Examples
polyroot(c(1, 2, 1))
round(polyroot(choose(8, 0:8)), 11) # guess what!
for (n1 in 1:4) print(polyroot(1:n1), digits = 4)