Mllib SVM实例
1、数据
数据格式为：标签, 特征1 特征2 特征3……
0 128:51 129:159 130:253 131:159 132:50 155:48 156:238 157:252 158:252 159:252 160:237 182:54 183:227 184:253 185:252 186:239 187:233 188:252 189:57 190:6 208:10 209:60 210:224 211:252 212:253 213:252 214:202 215:84 216:252 217:253 218:122 236:163 237:252 238:252 239:252 240:253 241:252 242:252 243:96 244:189 245:253 246:167 263:51 264:238 265:253 266:253 267:190 268:114 269:253 270:228 271:47 272:79 273:255 274:168 290:48 291:238 292:252 293:252 294:179 295:12 296:75 297:121 298:21 301:253 302:243 303:50 317:38 318:165 319:253 320:233 321:208 322:84 329:253 330:252 331:165 344:7 345:178 346:252 347:240 348:71 349:19 350:28 357:253 358:252 359:195 372:57 373:252 374:252 375:63 385:253 386:252 387:195 400:198 401:253 402:190 413:255 414:253 415:196 427:76 428:246 429:252 430:112 441:253 442:252 443:148 455:85 456:252 457:230 458:25 467:7 468:135 469:253 470:186 471:12 483:85 484:252 485:223 494:7 495:131 496:252 497:225 498:71 511:85 512:252 513:145 521:48 522:165 523:252 524:173 539:86 540:253 541:225 548:114 549:238 550:253 551:162 567:85 568:252 569:249 570:146 571:48 572:29 573:85 574:178 575:225 576:253 577:223 578:167 579:56 595:85 596:252 597:252 598:252 599:229 600:215 601:252 602:252 603:252 604:196 605:130 623:28 624:199 625:252 626:252 627:253 628:252 629:252 630:233 631:145 652:25 653:128 654:252 655:253 656:252 657:141 658:37
1 159:124 160:253 161:255 162:63 186:96 187:244 188:251 189:253 190:62 214:127 215:251 216:251 217:253 218:62 241:68 242:236 243:251 244:211 245:31 246:8 268:60 269:228 270:251 271:251 272:94 296:155 297:253 298:253 299:189 323:20 324:253 325:251 326:235 327:66 350:32 351:205 352:253 353:251 354:126 378:104 379:251 380:253 381:184 382:15 405:80 406:240 407:251 408:193 409:23 432:32 433:253 434:253 435:253 436:159 460:151 461:251 462:251 463:251 464:39 487:48 488:221 489:251 490:251 491:172 515:234 516:251 517:251 518:196 519:12 543:253 544:251 545:251 546:89 570:159 571:255 572:253 573:253 574:31 597:48 598:228 599:253 600:247 601:140 602:8 625:64 626:251 627:253 628:220 653:64 654:251 655:253 656:220 681:24 682:193 683:253 684:220
……
2、代码
1 //1 读取样本数据
2
3 val data_path = "/user/tmp/sample_libsvm_data.txt"
4
5 val examples = MLUtils.loadLibSVMFile(sc, data_path).cache()
6
7 //2 样本数据划分训练样本与测试样本
8
9 val splits = examples.randomSplit(Array(0.6, 0.4), seed = 11L)
10
11 val training = splits(0).cache()
12
13 val test = splits(1)
14
15 val numTraining = training.count()
16
17 val numTest = test.count()
18
19 println(s"Training: $numTraining, test: $numTest.")
20
21 //3 新建SVM模型，并设置训练参数
22
23 val numIterations = 1000
24
25 val stepSize = 1
26
27 val miniBatchFraction = 1.0
28
29 val model = SVMWithSGD.train(training, numIterations, stepSize, miniBatchFraction)
30 //4 对测试样本进行测试
31
32 val prediction = model.predict(test.map(_.features))
33
34 val predictionAndLabel = prediction.zip(test.map(_.label))
35
36 //5 计算测试误差
37
38 val metrics = new MulticlassMetrics(predictionAndLabel)
39
40 val precision = metrics.precision
41
42 println("Precision = " + precision)