19 lines
499 B
Scala
19 lines
499 B
Scala
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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 sqrt_stream(value: Double): LazyList[Double] = {
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def helper(target: Double, approx: Double): LazyList[Double] = {
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approx #:: helper(target, approx - (sqr(approx) - target) / (2 * approx))
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}
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helper(value, value)
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}
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sqrt_stream(2).take(10).toList
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def threshold(list: LazyList[Double], thresh: Double) = {
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list.zip(list.drop(1)).filter(p => math.abs(p._2 - p._1) < thresh).head._2
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}
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threshold(sqrt_stream(2), 1e-15) |