23 lines
453 B
Scheme
23 lines
453 B
Scheme
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(define (cuberoot_iter new_guess last_guess x)
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(if (good_enough? new_guess last_guess)
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new_guess
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(cuberoot_iter (improve new_guess x) new_guess x)
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)
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)
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(define (improve guess x)
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(/ (+ (/ x (* guess guess)) (* 2 guess)) 3))
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(define (good_enough? guess last_guess)
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(< (absolute (- guess last_guess)) 0.000000000000001))
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(define (absolute x)
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(if (< x 0)
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(- 0 x)
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x))
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(define (cbrt x) (cuberoot_iter (/ x 2.0) x x))
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(print (cbrt 27))
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