|
| 1 | +/* |
| 2 | + * Copyright (c) 2025. Phasmid Software |
| 3 | + */ |
| 4 | + |
| 5 | +package com.phasmidsoftware.number.cats |
| 6 | + |
| 7 | +import com.phasmidsoftware.number.cats.ErrorCommutativeMonoid._ |
| 8 | +import com.phasmidsoftware.number.core.inner.{PureNumber, Value} |
| 9 | +import com.phasmidsoftware.number.core.{AbsoluteFuzz, FuzzyNumber, Gaussian, Number, RelativeFuzz} |
| 10 | + |
| 11 | +/** |
| 12 | + * Usage-focused examples for the error metric Monoid instances. |
| 13 | + * |
| 14 | + * These tests are intentionally lightweight demonstrations rather than law checks. |
| 15 | + */ |
| 16 | +class ErrorCommutativeMonoidFuncSpec extends AnyFlatSpec with Matchers { |
| 17 | + |
| 18 | + behavior of "Abstracting advocacy communication into lawful scalar folding" |
| 19 | + |
| 20 | + |
| 21 | + |
| 22 | + it should "match decoupled parallel error folding with direct Number addition (all addition)" in { |
| 23 | + implicit val ec: ExecutionContext = ExecutionContext.global |
| 24 | + |
| 25 | + // Build many fuzzy addends: same nominal 1.2 with absolute Gaussian sigma 0.05 |
| 26 | + val terms: List[Number] = List.fill(2000) { |
| 27 | + FuzzyNumber(Value.fromDouble(Some(1.2)), PureNumber, Some(AbsoluteFuzz(0.05, Gaussian))) |
| 28 | + } |
| 29 | + |
| 30 | + // 1) Traditional: add fuzzy Numbers directly (measure time) |
| 31 | + val (accumulated: Number, tSeqMs) = 1.times { |
| 32 | + terms.tail.foldLeft(terms.head)(_ doAdd _) |
| 33 | + } |
| 34 | + |
| 35 | + val actualNominal = accumulated.toNominalDouble.getOrElse(Double.NaN) |
| 36 | + val actualAbs = accumulated match { |
| 37 | + case f: FuzzyNumber => f.fuzz.collect { case AbsoluteFuzz(m: Double, Gaussian) => m }.getOrElse(Double.NaN) |
| 38 | + case _ => Double.NaN |
| 39 | + } |
| 40 | + |
| 41 | + // 2) Decoupled parallel: nominal sum and sigma folding run independently |
| 42 | + val ((decoupledNominal, decoupledSigma), tParMs) = 1.times { |
| 43 | + val fNominal: Future[Double] = Future { terms.flatMap(_.toNominalDouble).sum } |
| 44 | + val fSigma: Future[Double] = Future { |
| 45 | + val sigmas = terms.map { |
| 46 | + case f: FuzzyNumber => f.fuzz.collect { case AbsoluteFuzz(m: Double, Gaussian) => m }.getOrElse(0.0) |
| 47 | + case _ => 0.0 |
| 48 | + } |
| 49 | + sigmas.foldLeft(AbsSigma.zero)(_ |+| AbsSigma(_)).value |
| 50 | + } |
| 51 | + val a = Await.result(fNominal, 5.seconds) |
| 52 | + val b = Await.result(fSigma, 5.seconds) |
| 53 | + (a, b) |
| 54 | + } |
| 55 | + |
| 56 | + val decoupled: Number = FuzzyNumber(Value.fromDouble(Some(decoupledNominal)), PureNumber, Some(AbsoluteFuzz(decoupledSigma, Gaussian))) |
| 57 | + |
| 58 | + val decoupledAbs = decoupled match { |
| 59 | + case f: FuzzyNumber => f.fuzz.collect { case AbsoluteFuzz(m: Double, Gaussian) => m }.getOrElse(Double.NaN) |
| 60 | + case _ => Double.NaN |
| 61 | + } |
| 62 | + |
| 63 | + // Compare nominal and absolute sigma |
| 64 | + actualNominal shouldBe decoupledNominal +- 1e-9 |
| 65 | + actualAbs shouldBe decoupledAbs +- 1e-9 |
| 66 | + |
| 67 | + // And new method should be faster (or equal) than traditional |
| 68 | + // NOTE: simple wall-clock comparison; if flaky in CI, relax or increase data size |
| 69 | + // tParMs: 72.449458, tSeqMs: 194.883 |
| 70 | + println(s"tParMs: $tParMs, tSeqMs: $tSeqMs") |
| 71 | + assert(tParMs <= tSeqMs, s"decoupled parallel folding should be faster: par=${tParMs}ms vs seq=${tSeqMs}ms") |
| 72 | + } |
| 73 | + |
| 74 | + // CONSIDER this test is slow. We might want to tag it as Slow (or perhaps try to speed it up) |
| 75 | + it should "match decoupled parallel error folding with direct Number multiplication (all multiplication)" in { |
| 76 | + implicit val ec: ExecutionContext = ExecutionContext.global |
| 77 | + |
| 78 | + // Build many fuzzy addends: same nominal 1.2 with absolute Gaussian sigma 0.05 |
| 79 | + val terms: List[Number] = List.fill(2000) { |
| 80 | + FuzzyNumber(Value.fromDouble(Some(1.1)), PureNumber, Some(RelativeFuzz(0.05, Gaussian))) |
| 81 | + } |
| 82 | + |
| 83 | + // 1) Traditional: multiply fuzzy Numbers directly (measure time) |
| 84 | + val (accumulated: Number, tSeqMs) = 1.times { |
| 85 | + terms.tail.foldLeft(terms.head)(_ doMultiply _) |
| 86 | + } |
| 87 | + |
| 88 | + val actualNominal = accumulated.toNominalDouble.getOrElse(Double.NaN) |
| 89 | + val actualRel = accumulated match { |
| 90 | + case f: FuzzyNumber => f.fuzz.collect { case RelativeFuzz(m: Double, Gaussian) => m }.getOrElse(Double.NaN) |
| 91 | + case _ => Double.NaN |
| 92 | + } |
| 93 | + |
| 94 | + // 2) Decoupled parallel: nominal product and sigma folding run independently |
| 95 | + val ((decoupledNominal, decoupledSigma), tParMs) = 1.times { |
| 96 | + val fNominal: Future[Double] = Future { |
| 97 | + val headNominal = terms.headOption.flatMap(_.toNominalDouble).getOrElse(Double.NaN) |
| 98 | + terms.tail.foldLeft(headNominal) { (acc, n) => |
| 99 | + acc * n.toNominalDouble.getOrElse(1.0) |
| 100 | + } |
| 101 | + } |
| 102 | + val fSigma: Future[Double] = Future { |
| 103 | + // Sequential combination, relative basis propagation: r_xy^2 = r_x^2 + r_y^2 + r_x r_y |
| 104 | + def combineRel(r1: Double, r2: Double): Double = { |
| 105 | + val a = r1; val b = r2 |
| 106 | + math.sqrt(a * a + b * b + a * b) |
| 107 | + } |
| 108 | + val sigmas = terms.map { |
| 109 | + case f: FuzzyNumber => f.fuzz.collect { case RelativeFuzz(m: Double, Gaussian) => m }.getOrElse(0.0) |
| 110 | + case _ => 0.0 |
| 111 | + } |
| 112 | + sigmas.foldLeft(0.0)(combineRel) |
| 113 | + } |
| 114 | + val a = Await.result(fNominal, 5.seconds) |
| 115 | + val b = Await.result(fSigma, 5.seconds) |
| 116 | + (a, b) |
| 117 | + } |
| 118 | + |
| 119 | + val decoupled: Number = FuzzyNumber(Value.fromDouble(Some(decoupledNominal)), PureNumber, Some(RelativeFuzz(decoupledSigma, Gaussian))) |
| 120 | + |
| 121 | + val decoupledRel = decoupled match { |
| 122 | + case f: FuzzyNumber => f.fuzz.collect { case RelativeFuzz(m: Double, Gaussian) => m }.getOrElse(Double.NaN) |
| 123 | + case _ => Double.NaN |
| 124 | + } |
| 125 | + |
| 126 | + // Compare nominal and relative sigma |
| 127 | + math.abs(actualNominal - decoupledNominal) / math.abs(actualNominal) should be < 1e-12 |
| 128 | + actualRel shouldBe decoupledRel +- 1e-1 |
| 129 | + |
| 130 | + // And new method should be faster (or equal) than traditional |
| 131 | + // NOTE: simple wall-clock comparison; if flaky in CI, relax or increase data size |
| 132 | + // tParMs: 5.240125, tSeqMs: 7731.776417 |
| 133 | + println(s"tParMs: $tParMs, tSeqMs: $tSeqMs") |
| 134 | + assert(tParMs <= tSeqMs, s"decoupled parallel folding should be faster: par=${tParMs}ms vs seq=${tSeqMs}ms") |
| 135 | + } |
| 136 | + |
| 137 | +} |
| 138 | + |
| 139 | + |
0 commit comments