以下是我将Weka功能保存到Scala文件中的方法：
val saver = new ArffSaver()
saver.setInstances(instances)
saver.setFile(new File(file))
saver.setDestination(new File(file))
saver.writeBatch()
在输出中我有这样的行：
{0 O,1 ?,2 ?,3 ?,4 ?,5 ?,6 ?,7 ?,8 ?,9 ?,10 ?,11 ?,12 ?,13 ?,14 ?,15 ?,16 ?,17 ?,18 ?,19 ?,20 ?,21 ?,22 ?,23 ?,24 ?,25 ?,26 ?,27 ?,28 ?,29 ?,30 ?,31 ?,32 ?,33 ?,34 ?,35 ?,36 ?,37 ?,38 ?,39 ?,40 ?,41 ?,42 ?,43 ?,44 ?,45 ?,46 ?,47 ?,48 ?,49 ?,50 ?,51 ?,52 ?,53 ?,54 ?,55 1,56 ?,57 ?,58 ?,59 ?,60 ?,61 ?,62 ?,63 ?,64 ?,65 ?,66 ?,67 ?,68 ?,69 ?,70 ?,71 ?,72 ?,73 ?,74 ?,75 ?,76 ?,77 ?,78 ?,79 ?,80 ?,81 ?,82 ?,83 ?,84 ?,85 ?,86 ?,87 ?,88 ?,89 ?,90 ?,91 ?,92 ?,93 ?,94 ?,95 ?,96 ?,97 ?,98 ?,99 ?,100 ?,101 ?,102 ?,103 ?,104 ?,105 ?,106 ?,107 ?,108 ?,109 ?,110 ?,111 ?,112 ?,113 ?,114 ?,115 ?,116 ?,117 ?,118 ?,119 ?,120 ?,121 ?,122 ?,123 ?,124 ?,125 ?,126 ?,127 ?,128 ?,129 ?,130 ?,131 ?,132 ?,133 ?,134 ?,135 ?,136 ?,137 ?,138 ?,139 ?,140 1,141 ?,142 1,143 ?,144 1,145 1,146 ?,147 1,148 1,149 ?,150 ?,151 ?,152 ?,153 ?,154 ?,155 ?,156 ?,157 ?,158 ?,159 ?,160 ?,161 ?,162 ?,163 ?,164 ?,165 ?,166 ?,167 ?,168 ?,169 ?,170 ?,171 ?,172 ?,173 ?,174 ?,175 ?,176 ?,177 ?,178 ?,179 ?,180 ?,181 ?,182 ?,183 ?,184 ?,185 ?,186 ?,187 ?,188 ?,189 ?,190 ?,191 ?,192 ?,193 ?,194 ?,195 ?,196 ?,197 ?,198 ?,199 ?,200 ?,201 ?,202 ?,203 ?,204 ?,205 ?,206 ?,207 ?,208 ?,209 ?,210 ?,211 ?,212 ?,213 ?,214 ?,215 ?,216 ?,217 ?,218 ?,219 ?,220 ?,221 ?,222 ?,223 ?,224 ?,225 ?,226 ?,227 ?,228 ?,229 ?,230 ?,231 ?,232 ?,233 ?,234 ?,235 ?,236 ?,237 ?,238 ?,239 ?,240 ?,241 ?,242 ?,243 ?,244 ?,245 ?,246 ?,247 ?,248 ?,249 ?,250 ?,251 ?,252 ?,253 ?,254 ?,255 ?,256 ?,257 ?,258 ?,259 ?,260 ?,261 ?,262 ?,263 ?,264 ?,265 1,266 ?,267 ?,268 ?,269 1,270 ?,271 ?,272 ?,273 ?,274 ?,275 ?,276 ?,277 ?,278 ?,279 ?,280 ?,281 ?,282 ?,283 ?,284 ?,285 ?,286 ?,287 ?,288 ?,289 ?,290 ?,291 ?,292 ?,293 ?,294 ?,295 ?,296 ?,297 ?,298 ?,299 ?,300 ?,301 ?,302 ?,303 ?,304 ?,305 ?,306 ?,307 ?,308 ?,309 ?,310 ?,311 ?,312 ?,313 ?,314 ?,315 ?,316 ?,317 ?,318 ?,319 ?,320 ?,321 ?,322 ?,323 ?,324 ?,325 ?,326 ?,327 ?,328 ?,329 ?,330 ?,331 ?,332 ?,333 ?,334 ?,335 ?,336 ?,337 ?,338 ?,339 ?,340 ?,341 ?,342 ?,343 ?,344 ?,345 ?,346 ?,347 ?,348 ?,349 ?,350 ?,351 ?,352 ?,353 ?,354 ?,355 ?,356 ?,357 ?,358 ?,359 ?,360 ?,361 ?,362 ?,363 ?,364 ?,365 ?,366 ?,367 ?,368 ?,369 ?,370 ?,371 ?,372 ?,373 ?,374 ?,375 ?,376 ?,377 ?,378 ?,379 ?,380 ?,381 ?,382 ?,383 ?,384 ?,385 ?,386 ?,387 ?,388 ?,389 ?,390 ?,391 ?,392 ?,393 ?,394 ?,395 ?,396 ?,397 ?,398 ?,399 ?,400 ?,401 ?,402 ?,403 ?,404 ?,405 ?,406 ?,407 ?,408 ?,409 ?,410 ?,411 ?,412 ?,413 ?,414 ?,415 ?,416 ?,417 ?,418 ?,419 ?,420 ?,421 ?,422 ?,423 ?,424 ?,425 ?,426 ?,427 ?,428 ?,429 ?,430 ?,431 ?,432 ?,433 ?,434 ?,435 ?,436 ?,437 ?,438 ?,439 ?,440 ?,441 ?,442 ?,443 ?,444 ?,445 ?,446 ?,447 ?,448 ?,449 ?,450 ?,451 ?,452 ?,453 ?,454 ?,455 ?,456 ?,457 ?,458 ?,459 ?,460 ?,461 ?,462 ?,463 ?,464 ?,465 ?,466 ?,467 ?,468 ?,469 ?,470 ?,471 ?,472 ?,473 ?,474 ?,475 ?,476 ?,477 ?,478 ?,479 ?,480 ?,481 ?,482 ?,483 ?,484 ?,485 ?,486 ?,487 ?,488 ?,489 ?,490 ?,491 ?,492 ?,493 ?,494 ?,495 ?,496 ?,497 ?,498 ?,499 ?,500 ?,501 ?,502 ?,503 ?,504 ?,505 ?,506 ?,507 ?,508 ?,509 ?,510 ?,511 ?,512 ?,513 ?,514 ?,515 ?,516 ?,517 ?,518 ?,519 ?,520 1,521 ?,522 ?,523 ?,524 ?,525 ?,526 ?,527 ?,528 ?,529 ?,530 ?,531 ?,532 ?,533 ?,534 ?,535 ?,536 ?,537 ?,538 ?,539 ?,540 ?,541 ?,542 ?,543 ?,544 ?,545 ?,546 ?,547 ?,548 ?,549 ?,550 ?,551 ?,552 ?,553 ?,554 ?,555 ?,556 ?,557 ?,558 ?,559 ?,560 ?,561 ?,562 ?,563 ?,564 ?,565 ?,566 ?,567 ?,568 ?,569 ?,570 ?,571 ?,572 ?,573 ?,574 ?,575 ?,576 ?,577 ?,578 ?,579 ?,580 ?,581 ?,582 ?,583 ?,584 ?,585 ?,586 ?,587 ?,588 ?,589 ?,590 ?,591 ?,592 ?,593 ?,594 ?,595 ?,596 ?,597 ?,598 ?,599 ?,600 ?,601 ?,602 ?,603 ?,604 ?,605 ?,606 ?,607 ?,608 ?,609 ?,610 ?,611 ?,612 ?,613 ?,614 ?,615 ?,616 ?,617 ?,618 ?,619 ?,620 ?,621 ?,622 ?,623 ?,624 ?,625 ?,626 ?,627 ?,628 ?,629 ?,630 ?,631 ?,632 ?,633 ?,634 ?,635 ?,636 ?,637 ?,638 ?,639 ?,640 ?,641 ?,642 ?,643 ?,644 ?,645 ?,646 ?,647 ?,648 ?,649 ?,650 ?,651 ?,652 ?,653 ?,654 ?,655 ?,656 ?,657 ?,658 ?,659 ?,660 ?,661 ?,662 ?,663 ?,664 ?,665 ?,666 ?,667 ?,668 ?,669 ?,670 ?,671 ?,672 ?,673 ?,674 ?,675 ?,676 ?,677 ?,678 ?,679 ?,680 ?,681 ?,682 ?,683 ?,684 ?,685 ?,686 ?,687 ?,688 ?,689 ?,690 ?,691 ?,692 1,693 ?,694 ?,695 ?,696 ?,697 ?,698 ?,699 ?,700 ?,701 ?,702 ?,703 ?,704 ?,705 ?,706 ?,707 ?,708 ?,709 ?,710 ?,711 ?,712 ?,713 ?,714 ?,715 ?,716 ?,717 ?,718 ?,719 ?,720 ?,721 ?,722 ?,723 ?,724 ?,725 ?,726 ?,727 ?,728 ?,729 ?,730 ?,731 ?,732 ?,733 ?,734 ?,735 ?,736 ?,737 ?,738 ?,739 ?,740 ?,741 ?,742 ?,743 ?,744 ?,745 ?,746 ?,747 ?,748 ?,749 ?,750 ?,751 ?,752 ?,753 ?,754 ?,755 ?,756 ?,757 ?,758 ?,759 ?,760 ?,761 ?,762 ?,763 ?,764 ?,765 ?,766 ?,767 ?,768 ?,769 ?,770 ?,771 ?,772 ?,773 ?,774 ?,775 ?,776 ?,777 ?,778 ?,779 ?,780 ?,781 ?,782 ?,783 ?,784 ?,785 ?,786 ?,787 ?,788 ?,789 ?,790 ?,791 ?,792 ?,793 ?,794 ?,795 ?,796 ?,797 ?,798 ?,799 ?,800 ?,801 ?,802 ?,803 ?,804 ?,805 ?,806 ?,807 ?,808 ?,809 ?,810 ?,811 ?,812 ?,813 ?,814 ?,815 ?,816 ?,817 ?,818 ?,819 ?,820 ?,821 ?,822 ?,823 ?,824 ?,825 ?,826 ?,827 ?,828 ?,829 ?,830 ?,831 ?,832 ?,833 ?,834 ?,835 ?,836 ?,837 ?,838 ?,839 ?,840 ?,841 ?,842 ?,843 ?,844 ?,845 ?,846 ?,847 ?,848 ?,849 ?,850 ?,851 ?,852 ?,853 ?,854 ?,855 ?,856 ?,857 ?,858 ?,859 ?,860 ?,861 ?,862 ?,863 ?,864 ?,865 ?,866 ?,867 ?,868 ?,869 ?,870 ?,871 ?,872 ?,873 ?,874 ?,875 ?,876 ?,877 ?,878 ?,879 ?,880 ?,881 ?,882 ?,883 ?,884 ?,885 ?,886 ?,887 ?,888 ?,889 ?,890 ?,891 ?,892 ?,893 ?,894 ?,895 ?,896 ?,897 ?,898 ?,899 ?,900 ?,901 ?,902 ?,903 ?,904 ?,905 ?,906 ?,907 ?,908 ?,909 ?,910 ?,911 ?,912 ?,913 ?,914 ?,915 ?,916 ?,917 ?,918 ?,919 ?,920 ?,921 ?,922 ?,923 ?,924 ?,925 ?,926 ?,927 ?,928 ?,929 ?,930 ?,931 ?,932 ?,933 ?,934 ?,935 ?,936 ?,937 ?,938 ?,939 ?,940 ?,941 ?,942 ?,943 ?,944 ?,945 ?,946 ?,947 ?,948 ?,949 ?,950 ?,951 ?,952 ?,953 ?,954 ?,955 ?,956 ?,957 ?,958 ?,959 ?,960 ?,961 ?,962 ?,963 ?,964 ?,965 ?,966 ?,967 ?,968 ?,969 ?,970 ?,971 ?,972 ?,973 ?,974 ?,975 ?,976 ?,977 ?,978 ?,979 ?,980 ?,981 ?,982 ?,983 ?,984 ?,985 ?,986 ?,987 ?,988 ?,989 ?,990 ?,991 ?,992 ?,993 ?,994 ?,995 ?,996 ?,997 ?,998 ?,999 ?,1000 ?,1001 ?,1002 ?,1003 ?,1004 ?,1005 ?,1006 ?,1007 ?,1008 ?,1009 ?,1010 ?,1011 ?,1012 ?,1013 ?,1014 ?,1015 ?,1016 ?,1017 ?,1018 ?,1019 ?,1020 ?,1021 ?,1022 ?,1023 ?,1024 ?,1025 ?,1026 ?,1027 ?,1028 ?,1029 ?,1030 ?,1031 ?,1032 ?,1033 ?,1034 ?,1035 ?,1036 ?,1037 ?,1038 ?,1039 ?,1040 ?,1041 ?,1042 ?,1043 ?,1044 ?,1045 ?,1046 ?,1047 ?,1048 ?,1049 ?,1050 ?,1051 ?,1052 ?,1053 ?,1054 ?,1055 ?,1056 ?,1057 ?,1058 ?,1059 ?,1060 ?,1061 ?,1062 ?,1063 ?,1064 ?,1065 ?,1066 ?,1067 ?,1068 ?,1069 ?,1070 ?,1071 ?,1072 ?,1073 ?,1074 ?,1075 ?,1076 ?,1077 ?,1078 ?,1079 ?,1080 ?,1081 ?,1082 ?,1083 ?,1084 ?,1085 ?,1086 ?,1087 ?,1088 ?,1089 ?,1090 ?,1091 ?,1092 ?,1093 ?,1094 ?,1095 ?,1096 ?,1097 ?,1098 ?,1099 ?,1100 ?,1101 ?,1102 ?,1103 ?,1104 ?,1105 ?,1106 ?,1107 ?,1108 ?,1109 ?,1110 ?,1111 ?,1112 ?,1113 ?,1114 ?,1115 ?,1116 ?,1117 ?,1118 ?,1119 ?,1120 ?,1121 ?,1122 ?,1123 ?,1124 ?,1125 ?,1126 ?,1127 ?,1128 ?,1129 ?,1130 ?,1131 ?,1132 ?,1133 ?,1134 ?,1135 ?,1136 ?,1137 ?,1138 ?,1139 ?,1140 ?,1141 ?,1142 ?,1143 ?,1144 ?,1145 ?,1146 ?,1147 ?,1148 ?,1149 ?,1150 ?,1151 ?,1152 ?,1153 ?,1154 ?,1155 ?,1156 ?,1157 ?,1158 ?,1159 ?,1160 ?,1161 ?,1162 ?,1163 ?,1164 ?,1165 ?,1166 ?,1167 ?,1168 ?,1169 ?,1170 ?,1171 ?,1172 ?,1173 ?,1174 ?,1175 ?,1176 ?,1177 ?,1178 ?,1179 ?,1180 ?,1181 ?,1182 ?,1183 ?,1184 ?,1185 ?,1186 ?,1187 ?,1188 ?,1189 ?,1190 ?,1191 ?,1192 ?,1193 ?,1194 ?,1195 ?,1196 ?,1197 ?,1198 ?,1199 ?,1200 ?,1201 ?,1202 ?,1203 ?,1204 ?,1205 ?,1206 ?,1207 ?,1208 ?,1209 ?,1210 ?,1211 ?,1212 ?,1213 ?,1214 ?,1215 ?,1216 ?,1217 ?,1218 ?,1219 ?,1220 ?,1221 ?,1222 ?,1223 ?,1224 ?,1225 ?,1226 ?,1227 ?,1228 ?,1229 ?,1230 ?,1231 ?,1232 ?,1233 ?,1234 ?,1235 ?,1236 ?,1237 ?,1238 ?,1239 ?,1240 ?,1241 ?,1242 ?,1243 ?,1244 ?,1245 ?,1246 ?,1247 ?,1248 ?,1249 ?,1250 ?,1251 ?,1252 ?,1253 ?,1254 ?,1255 ?,1256 ?,1257 ?,1258 ?,1259 ?,1260 ?,1261 ?,1262 ?,1263 ?,1264 ?,1265 ?,1266 ?,1267 ?,1268 ?,1269 ?,1270 ?,1271 ?,1272 ?,1273 ?,1274 ?,1275 ?,1276 ?,1277 ?,1278 ?,1279 ?,1280 ?,1281 ?,1282 ?,1283 ?,1284 ?,1285 ?,1286 ?,1287 ?,1288 ?,1289 ?,1290 ?,1291 ?,1292 ?,1293 ?,1294 ?,1295 ?,1296 ?,1297 ?,1298 ?,1299 ?,1300 ?,1301 ?,1302 ?,1303 ?,1304 ?,1305 ?,1306 ?,1307 ?,1308 ?,1309 ?,1310 ?,1311 ?,1312 ?,1313 ?,1314 ?,1315 ?,1316 ?,1317 ?,1318 ?,1319 ?,1320 ?,1321 ?,1322 ?,1323 ?,1324 ?,1325 ?,1326 ?,1327 ?,1328 ?,1329 ?,1330 ?,1331 ?,1332 ?,1333 ?,1334 ?,1335 ?,1336 ?,1337 ?,1338 ?,1339 ?,1340 ?,1341 ?,1342 ?,1343 ?,1344 ?,1345 ?,1346 ?,1347 ?,1348 ?,1349 ?,1350 ?,1351 ?,1352 ?,1353 ?,1354 ?,1355 ?,1356 ?,1357 ?,1358 ?,1359 ?,1360 ?,1361 ?,1362 ?,1363 ?,1364 ?,1365 ?,1366 ?,1367 ?,1368 ?,1369 ?,1370 ?,1371 ?,1372 ?,1373 ?,1374 ?,1375 ?,1376 ?,1377 ?,1378 ?,1379 ?,1380 ?,1381 ?,1382 ?,1383 ?,1384 ?,1385 ?,1386 ?,1387 ?,1388 ?,1389 ?,1390 ?,1391 ?,1392 ?,1393 ?,1394 ?,1395 ?,1396 ?,1397 ?,1398 ?,1399 ?,1400 ?,1401 ?,1402 ?,1403 ?,1404 ?,1405 ?,1406 ?,1407 ?,1408 ?,1409 ?,1410 ?,1411 ?,1412 ?,1413 ?,1414 ?,1415 ?,1416 ?,1417 ?,1418 ?,1419 ?,1420 ?,1421 ?,1422 ?,1423 ?,1424 ?,1425 ?,1426 ?,1427 ?,1428 ?,1429 ?,1430 ?,1431 ?,1432 ?,1433 ?,1434 ?,1435 ?,1436 ?,1437 ?,1438 ?,1439 ?,1440 ?,1441 ?,1442 ?,1443 ?,1444 ?,1445 ?,1446 ?,1447 ?,1448 ?,1449 ?,1450 ?,1451 ?,1452 ?,1453 ?,1454 ?,1455 ?,1456 ?,1457 ?,1458 ?,1459 ?,1460 ?,1461 ?,1462 ?,1463 ?,1464 ?,1465 ?,1466 1,1467 1,1468 1,1469 1,1470 1,1471 ?,1472 ?,1473 ?,1474 ?,1475 ?,1476 ?,1477 ?,1478 ?,1479 ?,1480 ?,1481 ?,1482 ?,1483 ?,1484 ?,1485 ?,1486 ?,1487 ?,1488 ?,1489 ?,1490 ?,1491 ?,1492 ?,1493 ?,1494 ?,1495 ?,1496 ?,1497 ?,1498 ?,1499 ?,1500 ?,1501 ?}
是高度稀疏的特征向量（即许多值是“？”）。 任何想法如何以稀疏格式保存它？ （即只写已知特征）
答案 0 :(得分：0)
使用：
instances.numAttributes()
然后使用循环可以获得所有属性：
instances.attribute(x).toString()
（这是java代码）