24 lines
483 B
Racket
24 lines
483 B
Racket
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(define (sqrt-iter guess guess-prev x)
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(if (good-enough? guess guess-prev)
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guess
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(sqrt-iter (improve guess x) guess
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x)))
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(define (improve guess x)
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(average guess (/ x guess)))
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(define (average x y)
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(/ (+ x y) 2))
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(define (good-enough? guess guess-prev)
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(< (abs (- guess guess-prev)) 0.001))
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(define (sqrt-new x)
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(if (= x 0) x (sqrt-iter 1.0 999 x)))
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(sqrt-new 16)
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(sqrt-new 1.0004)
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(sqrt-new 1)
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(sqrt-new 134895724398)
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(sqrt-new 0)
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