| // Copyright ©2017 The Gonum Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package distuv |
| |
| import ( |
| "math" |
| "sort" |
| "testing" |
| |
| "golang.org/x/exp/rand" |
| |
| "gonum.org/v1/gonum/floats/scalar" |
| ) |
| |
| func TestUniformProb(t *testing.T) { |
| t.Parallel() |
| for _, test := range []struct { |
| min, max, x, want float64 |
| }{ |
| {0, 1, 1, 1}, |
| {2, 4, 0, 0}, |
| {2, 4, 5, 0}, |
| {2, 4, 3, 0.5}, |
| {0, 100, 1, 0.01}, |
| {-1, 1, -1.5, 0}, |
| {-1, 1, 1.5, 0}, |
| } { |
| u := Uniform{test.min, test.max, nil} |
| pdf := u.Prob(test.x) |
| if !scalar.EqualWithinAbsOrRel(pdf, test.want, 1e-15, 1e-15) { |
| t.Errorf("PDF mismatch, x = %v, min = %v, max = %v. Got %v, want %v", test.x, test.min, test.max, pdf, test.want) |
| } |
| logWant := math.Log(test.want) |
| logPdf := u.LogProb(test.x) |
| if !scalar.EqualWithinAbsOrRel(logPdf, logWant, 1e-15, 1e-15) { |
| t.Errorf("Log PDF mismatch, x = %v, min = %v, max = %v. Got %v, want %v", test.x, test.min, test.max, logPdf, logWant) |
| } |
| } |
| } |
| |
| func TestUniformCDFSurvival(t *testing.T) { |
| t.Parallel() |
| for _, test := range []struct { |
| min, max, x, want float64 |
| }{ |
| {0, 1, 1, 1}, |
| {0, 100, 100, 1}, |
| {0, 100, 0, 0}, |
| {0, 100, 50, 0.5}, |
| {0, 50, 10, 0.2}, |
| {-1, 1, -1.5, 0}, |
| {-1, 1, 1.5, 1}, |
| } { |
| u := Uniform{test.min, test.max, nil} |
| cdf := u.CDF(test.x) |
| if !scalar.EqualWithinAbsOrRel(cdf, test.want, 1e-15, 1e-15) { |
| t.Errorf("CDF mismatch, x = %v, min = %v, max = %v. Got %v, want %v", test.x, test.min, test.max, cdf, test.want) |
| } |
| survival := u.Survival(test.x) |
| if !scalar.EqualWithinAbsOrRel(survival, 1-test.want, 1e-15, 1e-15) { |
| t.Errorf("CDF mismatch, x = %v, min = %v, max = %v. Got %v, want %v", test.x, test.min, test.max, survival, 1-test.want) |
| } |
| } |
| } |
| |
| func TestUniform(t *testing.T) { |
| t.Parallel() |
| src := rand.New(rand.NewSource(1)) |
| for i, b := range []Uniform{ |
| {1, 2, src}, |
| {0, 100, src}, |
| {50, 60, src}, |
| } { |
| testUniform(t, b, i) |
| } |
| } |
| |
| func testUniform(t *testing.T, u Uniform, i int) { |
| const ( |
| tol = 1e-2 |
| n = 1e5 |
| bins = 50 |
| ) |
| x := make([]float64, n) |
| generateSamples(x, u) |
| sort.Float64s(x) |
| |
| testRandLogProbContinuous(t, i, 0, x, u, tol, bins) |
| checkMean(t, i, x, u, tol) |
| checkVarAndStd(t, i, x, u, tol) |
| checkExKurtosis(t, i, x, u, 7e-2) |
| checkProbContinuous(t, i, x, u.Min, u.Max, u, 1e-10) |
| checkQuantileCDFSurvival(t, i, x, u, 1e-2) |
| checkEntropy(t, i, x, u, tol) |
| checkSkewness(t, i, x, u, tol) |
| checkMedian(t, i, x, u, tol) |
| testDerivParam(t, &u) |
| } |
| |
| func TestUniformScore(t *testing.T) { |
| t.Parallel() |
| u := Uniform{0, 1, nil} |
| for _, test := range []struct { |
| x, wantMin, wantMax float64 |
| }{ |
| {-0.001, math.NaN(), math.NaN()}, |
| {0, math.NaN(), -1}, |
| {1, 1, math.NaN()}, |
| {1.001, math.NaN(), math.NaN()}, |
| } { |
| score := u.Score(nil, test.x) |
| if !scalar.Same(score[0], test.wantMin) { |
| t.Errorf("Score[0] mismatch for at %g: got %v, want %g", test.x, score[0], test.wantMin) |
| } |
| if !scalar.Same(score[1], test.wantMax) { |
| t.Errorf("Score[1] mismatch for at %g: got %v, want %g", test.x, score[1], test.wantMax) |
| } |
| } |
| } |
| |
| func TestUniformScoreInput(t *testing.T) { |
| t.Parallel() |
| u := Uniform{0, 1, nil} |
| scoreInput := u.ScoreInput(0.5) |
| if scoreInput != 0 { |
| t.Errorf("Mismatch in input score for U(0, 1) at x == 0.5: got %v, want 0", scoreInput) |
| } |
| xs := []float64{-0.0001, 0, 1, 1.0001} |
| for _, x := range xs { |
| scoreInput = u.ScoreInput(x) |
| if !math.IsNaN(scoreInput) { |
| t.Errorf("Expected NaN score input for U(0, 1) at x == %g, got %v", x, scoreInput) |
| } |
| } |
| } |