Newton's method

Source: R/newton.R

Use Newton's method to find real roots

newton(f, fp, x, tol = 0.001, m = 100)

Arguments

f

function to integrate
fp

function representing the derivative of f
x

an initial estimate of the root
tol

the error tolerance
m

the maximum number of iterations

Value

the real root found

Details

Newton's method finds real roots of a function, but requires knowing the function derivative. It will return when the interval between them is less than tol, the error tolerance. However, this implementation also stops after m iterations.

See also

Other optimz: bisection(), goldsect, gradient, hillclimbing(), sa(), secant()

Examples

f <- function(x) { x^3 - 2 * x^2 - 159 * x - 540 }
fp <- function(x) {3 * x^2 - 4 * x - 159 }
newton(f, fp, 1)
#> [1] -4