20 lines
431 B
Scheme
20 lines
431 B
Scheme
;;; -*-Scheme-*-
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(define (sqrt x)
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(define (good-enough? guess)
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(< (abs (- (square guess) x)) 0.001))
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(define (improve guess)
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(average guess (/ x guess)))
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(define (sqrt-iter guess)
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(if (good-enough? guess)
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guess
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(sqrt-iter (improve guess))))
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(sqrt-iter 1))
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(define (square x) (* x x))
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(define (average x y) (/ (+ x y) 2))
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(define (abs x) (if (negative? x) (- x) x))
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(print (sqrt 2))
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(print (sqrt 4))
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