RosettaCodeData/Task/Nth-root/Scheme/nth-root.ss

19 lines
514 B
Scheme

(define (root number degree tolerance)
(define (good-enough? next guess)
(< (abs (- next guess)) tolerance))
(define (improve guess)
(/ (+ (* (- degree 1) guess) (/ number (expt guess (- degree 1)))) degree))
(define (*root guess)
(let ((next (improve guess)))
(if (good-enough? next guess)
guess
(*root next))))
(*root 1.0))
(display (root (expt 2 10) 10 0.1))
(newline)
(display (root (expt 2 10) 10 0.01))
(newline)
(display (root (expt 2 10) 10 0.001))
(newline)