| // Copyright ©2016 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" |
| "math/rand" |
| "sort" |
| "testing" |
| |
| "gonum.org/v1/gonum/floats" |
| ) |
| |
| func TestBetaProb(t *testing.T) { |
| // Values a comparison with scipy |
| for _, test := range []struct { |
| x, alpha, beta, want float64 |
| }{ |
| {0.1, 2, 0.5, 0.079056941504209499}, |
| {0.5, 1, 5.1, 0.29740426605235754}, |
| {0.1, 0.5, 0.5, 1.0610329539459691}, |
| {1, 0.5, 0.5, math.Inf(1)}, |
| {-1, 0.5, 0.5, 0}, |
| } { |
| pdf := Beta{Alpha: test.alpha, Beta: test.beta}.Prob(test.x) |
| if !floats.EqualWithinAbsOrRel(pdf, test.want, 1e-10, 1e-10) { |
| t.Errorf("Pdf mismatch. Got %v, want %v", pdf, test.want) |
| } |
| } |
| } |
| |
| func TestBetaRand(t *testing.T) { |
| src := rand.New(rand.NewSource(1)) |
| for i, b := range []Beta{ |
| {Alpha: 0.5, Beta: 0.5, Source: src}, |
| {Alpha: 5, Beta: 1, Source: src}, |
| {Alpha: 2, Beta: 2, Source: src}, |
| {Alpha: 2, Beta: 5, Source: src}, |
| } { |
| testBeta(t, b, i) |
| } |
| } |
| |
| func testBeta(t *testing.T, b Beta, i int) { |
| tol := 1e-2 |
| const n = 1e6 |
| const bins = 10 |
| x := make([]float64, n) |
| generateSamples(x, b) |
| sort.Float64s(x) |
| |
| testRandLogProbContinuous(t, i, 0, x, b, tol, bins) |
| checkMean(t, i, x, b, tol) |
| checkVarAndStd(t, i, x, b, tol) |
| checkExKurtosis(t, i, x, b, 5e-2) |
| checkProbContinuous(t, i, x, b, 1e-3) |
| checkQuantileCDFSurvival(t, i, x, b, tol) |
| checkProbQuantContinuous(t, i, x, b, tol) |
| } |