25 lines
522 B
Scheme
25 lines
522 B
Scheme
#lang scheme
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; We dont have closures at the time of writing, but each func gets its own env
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; http://sarabander.github.io/sicp/html/1_002e1.xhtml#g_t1_002e1_002e7
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(define (sqrt-iter guess x)
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(if (good-enough? guess x) guess (sqrt-iter (improve guess x) 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 (square x)
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(* x x))
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(define (good-enough? guess x)
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(< (abs (- (square guess) x)) 0.001))
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(define (sqrt x)
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(sqrt-iter 1.0 x))
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(display (sqrt 2))
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