19 lines
428 B
Scala
19 lines
428 B
Scala
import scala.annotation.tailrec
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def THRESHOLD: Double = 0.0001
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def sqr(x: Double): Double = x * x
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def isGoodEnough(x: Double): Boolean = if (x < 0) x > THRESHOLD else x < THRESHOLD
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def improve(x: Double, approx: Double) = approx - (sqr(approx) - x) / (2 * approx)
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@tailrec
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def sqrt(x: Double, approx: Double): Double = if (
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isGoodEnough(sqr(approx) - x)
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) {
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approx
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} else {
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sqrt(x, improve(x, approx))
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}
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sqrt(612, 10)
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