copula (version 0.999-15)

polynEval: Evaluate Polynomials

Description

Evaluate a univariate polynomial at x (typically a vector), that is, compute, for a given vector of coefficients coef, the polynomial coef[1] + coef[2]*x + ... + coef[p+1]*x^p.

Usage

polynEval(coef, x)

Arguments

coef

numeric vector. If a vector, x can be an array and the result matches x.

x

numeric vector or array.

Value

numeric vector or array, with the same dimensions as x, containing the polynomial values $p(x)$.

Details

The stable Horner rule is used for evaluation.

Using the C code speeds up the already fast R code available in polyn.eval() in package sfsmisc.

See Also

For a much more sophisticated treatment of polynomials, use the polynom package (for example, evaluation can be done via predict.polynomial).

Examples

polynEval(c(1,-2,1), x = -2:7) # (x - 1)^2
polynEval(c(0, 24, -50, 35, -10, 1),
          x = matrix(0:5, 2,3)) # 5 zeros!