libgo/go/math/rand/regress_test.go

   1 // Copyright 2014 The Go Authors.  All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // Test that random number sequences generated by a specific seed
   6 // do not change from version to version.
   7 //
   8 // Do NOT make changes to the golden outputs. If bugs need to be fixed
   9 // in the underlying code, find ways to fix them that do not affect the
  10 // outputs.
  11
  12 package rand_test
  13
  14 import (
  15         "flag"
  16         "fmt"
  17         . "math/rand"
  18         "reflect"
  19         "testing"
  20 )
  21
  22 var printgolden = flag.Bool("printgolden", false, "print golden results for regression test")
  23
  24 func TestRegress(t *testing.T) {
  25         var int32s = []int32{1, 10, 32, 1 << 20, 1<<20 + 1, 1000000000, 1 << 30, 1<<31 - 2, 1<<31 - 1}
  26         var int64s = []int64{1, 10, 32, 1 << 20, 1<<20 + 1, 1000000000, 1 << 30, 1<<31 - 2, 1<<31 - 1, 1000000000000000000, 1 << 60, 1<<63 - 2, 1<<63 - 1}
  27         var permSizes = []int{0, 1, 5, 8, 9, 10, 16}
  28         r := New(NewSource(0))
  29
  30         rv := reflect.ValueOf(r)
  31         n := rv.NumMethod()
  32         p := 0
  33         if *printgolden {
  34                 fmt.Printf("var regressGolden = []interface{}{\n")
  35         }
  36         for i := 0; i < n; i++ {
  37                 m := rv.Type().Method(i)
  38                 mv := rv.Method(i)
  39                 mt := mv.Type()
  40                 if mt.NumOut() == 0 {
  41                         continue
  42                 }
  43                 if mt.NumOut() != 1 {
  44                         t.Fatalf("unexpected result count for r.%s", m.Name)
  45                 }
  46                 r.Seed(0)
  47                 for repeat := 0; repeat < 20; repeat++ {
  48                         var args []reflect.Value
  49                         var argstr string
  50                         if mt.NumIn() == 1 {
  51                                 var x interface{}
  52                                 switch mt.In(0).Kind() {
  53                                 default:
  54                                         t.Fatalf("unexpected argument type for r.%s", m.Name)
  55
  56                                 case reflect.Int:
  57                                         if m.Name == "Perm" {
  58                                                 x = permSizes[repeat%len(permSizes)]
  59                                                 break
  60                                         }
  61                                         big := int64s[repeat%len(int64s)]
  62                                         if int64(int(big)) != big {
  63                                                 r.Int63n(big) // what would happen on 64-bit machine, to keep stream in sync
  64                                                 if *printgolden {
  65                                                         fmt.Printf("\tskipped, // must run printgolden on 64-bit machine\n")
  66                                                 }
  67                                                 p++
  68                                                 continue
  69                                         }
  70                                         x = int(big)
  71
  72                                 case reflect.Int32:
  73                                         x = int32s[repeat%len(int32s)]
  74
  75                                 case reflect.Int64:
  76                                         x = int64s[repeat%len(int64s)]
  77                                 }
  78                                 argstr = fmt.Sprint(x)
  79                                 args = append(args, reflect.ValueOf(x))
  80                         }
  81                         out := mv.Call(args)[0].Interface()
  82                         if m.Name == "Int" || m.Name == "Intn" {
  83                                 out = int64(out.(int))
  84                         }
  85                         if *printgolden {
  86                                 var val string
  87                                 big := int64(1 << 60)
  88                                 if int64(int(big)) != big && (m.Name == "Int" || m.Name == "Intn") {
  89                                         // 32-bit machine cannot print 64-bit results
  90                                         val = "truncated"
  91                                 } else if reflect.TypeOf(out).Kind() == reflect.Slice {
  92                                         val = fmt.Sprintf("%#v", out)
  93                                 } else {
  94                                         val = fmt.Sprintf("%T(%v)", out, out)
  95                                 }
  96                                 fmt.Printf("\t%s, // %s(%s)\n", val, m.Name, argstr)
  97                         } else {
  98                                 want := regressGolden[p]
  99                                 if m.Name == "Int" {
 100                                         want = int64(int(uint(want.(int64)) << 1 >> 1))
 101                                 }
 102                                 if !reflect.DeepEqual(out, want) {
 103                                         t.Errorf("r.%s(%s) = %v, want %v", m.Name, argstr, out, want)
 104                                 }
 105                         }
 106                         p++
 107                 }
 108         }
 109         if *printgolden {
 110                 fmt.Printf("}\n")
 111         }
 112 }
 113
 114 var regressGolden = []interface{}{
 115         float64(4.668112973579268),    // ExpFloat64()
 116         float64(0.1601593871172866),   // ExpFloat64()
 117         float64(3.0465834105636),      // ExpFloat64()
 118         float64(0.06385839451671879),  // ExpFloat64()
 119         float64(1.8578917487258961),   // ExpFloat64()
 120         float64(0.784676123472182),    // ExpFloat64()
 121         float64(0.11225477361256932),  // ExpFloat64()
 122         float64(0.20173283329802255),  // ExpFloat64()
 123         float64(0.3468619496201105),   // ExpFloat64()
 124         float64(0.35601103454384536),  // ExpFloat64()
 125         float64(0.888376329507869),    // ExpFloat64()
 126         float64(1.4081362450365698),   // ExpFloat64()
 127         float64(1.0077753823151994),   // ExpFloat64()
 128         float64(0.23594100766227588),  // ExpFloat64()
 129         float64(2.777245612300007),    // ExpFloat64()
 130         float64(0.5202997830662377),   // ExpFloat64()
 131         float64(1.2842705247770294),   // ExpFloat64()
 132         float64(0.030307408362776206), // ExpFloat64()
 133         float64(2.204156824853721),    // ExpFloat64()
 134         float64(2.09891923895058),     // ExpFloat64()
 135         float32(0.94519615),           // Float32()
 136         float32(0.24496509),           // Float32()
 137         float32(0.65595627),           // Float32()
 138         float32(0.05434384),           // Float32()
 139         float32(0.3675872),            // Float32()
 140         float32(0.28948045),           // Float32()
 141         float32(0.1924386),            // Float32()
 142         float32(0.65533215),           // Float32()
 143         float32(0.8971697),            // Float32()
 144         float32(0.16735445),           // Float32()
 145         float32(0.28858566),           // Float32()
 146         float32(0.9026048),            // Float32()
 147         float32(0.84978026),           // Float32()
 148         float32(0.2730468),            // Float32()
 149         float32(0.6090802),            // Float32()
 150         float32(0.253656),             // Float32()
 151         float32(0.7746542),            // Float32()
 152         float32(0.017480763),          // Float32()
 153         float32(0.78707397),           // Float32()
 154         float32(0.7993937),            // Float32()
 155         float64(0.9451961492941164),   // Float64()
 156         float64(0.24496508529377975),  // Float64()
 157         float64(0.6559562651954052),   // Float64()
 158         float64(0.05434383959970039),  // Float64()
 159         float64(0.36758720663245853),  // Float64()
 160         float64(0.2894804331565928),   // Float64()
 161         float64(0.19243860967493215),  // Float64()
 162         float64(0.6553321508148324),   // Float64()
 163         float64(0.897169713149801),    // Float64()
 164         float64(0.16735444255905835),  // Float64()
 165         float64(0.2885856518054551),   // Float64()
 166         float64(0.9026048462705047),   // Float64()
 167         float64(0.8497802817628735),   // Float64()
 168         float64(0.2730468047134829),   // Float64()
 169         float64(0.6090801919903561),   // Float64()
 170         float64(0.25365600644283687),  // Float64()
 171         float64(0.7746542391859803),   // Float64()
 172         float64(0.017480762156647272), // Float64()
 173         float64(0.7870739563039942),   // Float64()
 174         float64(0.7993936979594545),   // Float64()
 175         int64(8717895732742165505),    // Int()
 176         int64(2259404117704393152),    // Int()
 177         int64(6050128673802995827),    // Int()
 178         int64(501233450539197794),     // Int()
 179         int64(3390393562759376202),    // Int()
 180         int64(2669985732393126063),    // Int()
 181         int64(1774932891286980153),    // Int()
 182         int64(6044372234677422456),    // Int()
 183         int64(8274930044578894929),    // Int()
 184         int64(1543572285742637646),    // Int()
 185         int64(2661732831099943416),    // Int()
 186         int64(8325060299420976708),    // Int()
 187         int64(7837839688282259259),    // Int()
 188         int64(2518412263346885298),    // Int()
 189         int64(5617773211005988520),    // Int()
 190         int64(2339563716805116249),    // Int()
 191         int64(7144924247938981575),    // Int()
 192         int64(161231572858529631),     // Int()
 193         int64(7259475919510918339),    // Int()
 194         int64(7373105480197164748),    // Int()
 195         int32(2029793274),             // Int31()
 196         int32(526058514),              // Int31()
 197         int32(1408655353),             // Int31()
 198         int32(116702506),              // Int31()
 199         int32(789387515),              // Int31()
 200         int32(621654496),              // Int31()
 201         int32(413258767),              // Int31()
 202         int32(1407315077),             // Int31()
 203         int32(1926657288),             // Int31()
 204         int32(359390928),              // Int31()
 205         int32(619732968),              // Int31()
 206         int32(1938329147),             // Int31()
 207         int32(1824889259),             // Int31()
 208         int32(586363548),              // Int31()
 209         int32(1307989752),             // Int31()
 210         int32(544722126),              // Int31()
 211         int32(1663557311),             // Int31()
 212         int32(37539650),               // Int31()
 213         int32(1690228450),             // Int31()
 214         int32(1716684894),             // Int31()
 215         int32(0),                      // Int31n(1)
 216         int32(4),                      // Int31n(10)
 217         int32(25),                     // Int31n(32)
 218         int32(310570),                 // Int31n(1048576)
 219         int32(857611),                 // Int31n(1048577)
 220         int32(621654496),              // Int31n(1000000000)
 221         int32(413258767),              // Int31n(1073741824)
 222         int32(1407315077),             // Int31n(2147483646)
 223         int32(1926657288),             // Int31n(2147483647)
 224         int32(0),                      // Int31n(1)
 225         int32(8),                      // Int31n(10)
 226         int32(27),                     // Int31n(32)
 227         int32(367019),                 // Int31n(1048576)
 228         int32(209005),                 // Int31n(1048577)
 229         int32(307989752),              // Int31n(1000000000)
 230         int32(544722126),              // Int31n(1073741824)
 231         int32(1663557311),             // Int31n(2147483646)
 232         int32(37539650),               // Int31n(2147483647)
 233         int32(0),                      // Int31n(1)
 234         int32(4),                      // Int31n(10)
 235         int64(8717895732742165505),    // Int63()
 236         int64(2259404117704393152),    // Int63()
 237         int64(6050128673802995827),    // Int63()
 238         int64(501233450539197794),     // Int63()
 239         int64(3390393562759376202),    // Int63()
 240         int64(2669985732393126063),    // Int63()
 241         int64(1774932891286980153),    // Int63()
 242         int64(6044372234677422456),    // Int63()
 243         int64(8274930044578894929),    // Int63()
 244         int64(1543572285742637646),    // Int63()
 245         int64(2661732831099943416),    // Int63()
 246         int64(8325060299420976708),    // Int63()
 247         int64(7837839688282259259),    // Int63()
 248         int64(2518412263346885298),    // Int63()
 249         int64(5617773211005988520),    // Int63()
 250         int64(2339563716805116249),    // Int63()
 251         int64(7144924247938981575),    // Int63()
 252         int64(161231572858529631),     // Int63()
 253         int64(7259475919510918339),    // Int63()
 254         int64(7373105480197164748),    // Int63()
 255         int64(0),                      // Int63n(1)
 256         int64(2),                      // Int63n(10)
 257         int64(19),                     // Int63n(32)
 258         int64(959842),                 // Int63n(1048576)
 259         int64(688912),                 // Int63n(1048577)
 260         int64(393126063),              // Int63n(1000000000)
 261         int64(89212473),               // Int63n(1073741824)
 262         int64(834026388),              // Int63n(2147483646)
 263         int64(1577188963),             // Int63n(2147483647)
 264         int64(543572285742637646),     // Int63n(1000000000000000000)
 265         int64(355889821886249464),     // Int63n(1152921504606846976)
 266         int64(8325060299420976708),    // Int63n(9223372036854775806)
 267         int64(7837839688282259259),    // Int63n(9223372036854775807)
 268         int64(0),                      // Int63n(1)
 269         int64(0),                      // Int63n(10)
 270         int64(25),                     // Int63n(32)
 271         int64(679623),                 // Int63n(1048576)
 272         int64(882178),                 // Int63n(1048577)
 273         int64(510918339),              // Int63n(1000000000)
 274         int64(782454476),              // Int63n(1073741824)
 275         int64(0),                      // Intn(1)
 276         int64(4),                      // Intn(10)
 277         int64(25),                     // Intn(32)
 278         int64(310570),                 // Intn(1048576)
 279         int64(857611),                 // Intn(1048577)
 280         int64(621654496),              // Intn(1000000000)
 281         int64(413258767),              // Intn(1073741824)
 282         int64(1407315077),             // Intn(2147483646)
 283         int64(1926657288),             // Intn(2147483647)
 284         int64(543572285742637646),     // Intn(1000000000000000000)
 285         int64(355889821886249464),     // Intn(1152921504606846976)
 286         int64(8325060299420976708),    // Intn(9223372036854775806)
 287         int64(7837839688282259259),    // Intn(9223372036854775807)
 288         int64(0),                      // Intn(1)
 289         int64(2),                      // Intn(10)
 290         int64(14),                     // Intn(32)
 291         int64(515775),                 // Intn(1048576)
 292         int64(839455),                 // Intn(1048577)
 293         int64(690228450),              // Intn(1000000000)
 294         int64(642943070),              // Intn(1073741824)
 295         float64(-0.28158587086436215), // NormFloat64()
 296         float64(0.570933095808067),    // NormFloat64()
 297         float64(-1.6920196326157044),  // NormFloat64()
 298         float64(0.1996229111693099),   // NormFloat64()
 299         float64(1.9195199291234621),   // NormFloat64()
 300         float64(0.8954838794918353),   // NormFloat64()
 301         float64(0.41457072128813166),  // NormFloat64()
 302         float64(-0.48700161491544713), // NormFloat64()
 303         float64(-0.1684059662402393),  // NormFloat64()
 304         float64(0.37056410998929545),  // NormFloat64()
 305         float64(1.0156889027029008),   // NormFloat64()
 306         float64(-0.5174422210625114),  // NormFloat64()
 307         float64(-0.5565834214413804),  // NormFloat64()
 308         float64(0.778320596648391),    // NormFloat64()
 309         float64(-1.8970718197702225),  // NormFloat64()
 310         float64(0.5229525761688676),   // NormFloat64()
 311         float64(-1.5515595563231523),  // NormFloat64()
 312         float64(0.0182029289376123),   // NormFloat64()
 313         float64(-0.6820951356608795),  // NormFloat64()
 314         float64(-0.5987943422687668),  // NormFloat64()
 315         []int{},                                                     // Perm(0)
 316         []int{0},                                                    // Perm(1)
 317         []int{0, 4, 1, 3, 2},                                        // Perm(5)
 318         []int{3, 1, 0, 4, 7, 5, 2, 6},                               // Perm(8)
 319         []int{5, 0, 3, 6, 7, 4, 2, 1, 8},                            // Perm(9)
 320         []int{4, 5, 0, 2, 6, 9, 3, 1, 8, 7},                         // Perm(10)
 321         []int{14, 2, 0, 8, 3, 5, 13, 12, 1, 4, 6, 7, 11, 9, 15, 10}, // Perm(16)
 322         []int{},                                                     // Perm(0)
 323         []int{0},                                                    // Perm(1)
 324         []int{3, 0, 1, 2, 4},                                        // Perm(5)
 325         []int{5, 1, 2, 0, 4, 7, 3, 6},                               // Perm(8)
 326         []int{4, 0, 6, 8, 1, 5, 2, 7, 3},                            // Perm(9)
 327         []int{8, 6, 1, 7, 5, 4, 3, 2, 9, 0},                         // Perm(10)
 328         []int{0, 3, 13, 2, 15, 4, 10, 1, 8, 14, 7, 6, 12, 9, 5, 11}, // Perm(16)
 329         []int{},                             // Perm(0)
 330         []int{0},                            // Perm(1)
 331         []int{0, 4, 2, 1, 3},                // Perm(5)
 332         []int{2, 1, 7, 0, 6, 3, 4, 5},       // Perm(8)
 333         []int{8, 7, 5, 3, 4, 6, 0, 1, 2},    // Perm(9)
 334         []int{1, 0, 2, 5, 7, 6, 9, 8, 3, 4}, // Perm(10)
 335         uint32(4059586549),                  // Uint32()
 336         uint32(1052117029),                  // Uint32()
 337         uint32(2817310706),                  // Uint32()
 338         uint32(233405013),                   // Uint32()
 339         uint32(1578775030),                  // Uint32()
 340         uint32(1243308993),                  // Uint32()
 341         uint32(826517535),                   // Uint32()
 342         uint32(2814630155),                  // Uint32()
 343         uint32(3853314576),                  // Uint32()
 344         uint32(718781857),                   // Uint32()
 345         uint32(1239465936),                  // Uint32()
 346         uint32(3876658295),                  // Uint32()
 347         uint32(3649778518),                  // Uint32()
 348         uint32(1172727096),                  // Uint32()
 349         uint32(2615979505),                  // Uint32()
 350         uint32(1089444252),                  // Uint32()
 351         uint32(3327114623),                  // Uint32()
 352         uint32(75079301),                    // Uint32()
 353         uint32(3380456901),                  // Uint32()
 354         uint32(3433369789),                  // Uint32()
 355 }