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with pointwise order. Using the pointwise order on functions one can concisely define other important notions, for instance:
97:, that is, operations defined on functions by applying the operations to function values separately for each point in the 17: 1606: 1566: 1176:, and any componentwise operation on vectors is the pointwise operation on functions corresponding to those vectors. 515: 1000: 932: 437: 1243:. Pointwise orders also inherit some properties of the underlying posets. For instance if A and B are 113: 1137: 1200: 789:
Componentwise operations are usually defined on vectors, where vectors are elements of the set
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The pointwise product with a scalar is usually written with the scalar term first. Thus, when
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are denoted by the same symbol. A similar definition is used for unary operations
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is used to indicate that a certain property is defined by considering each value
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can be turned into an algebraic structure of the same type in an analogous way.
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can be regarded as a function, and a vector is a tuple. Therefore, any vector
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Componentwise operations can be defined on matrices. Matrix addition, where
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Applying operations to functions in terms of values for each input "point"
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Pointwise sum (upper plot, violet) and product (green) of the functions
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G. Gierz, K. H. Hofmann, K. Keimel, J. D. Lawson, M. Mislove,
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The pointwise product or pointwise multiplication is:
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This article incorporates material from Pointwise on
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Important 1607:Mathematical terminology 1517: 1434:pointwise to a function 1127:{\displaystyle f:n\to K} 785:Componentwise operations 601:{\displaystyle \lambda } 1530:Gierz et al., p. xxxiii 1203:, the set of functions 362:The pointwise addition 121:(lower plot, blue) and 1509: 1425: 1386: 1333:pointwise relation is 1170: 1128: 1096: 1065: 988: 923: 896: 876: 856: 833: 810: 775: 751: 727: 673: 602: 580: 502: 422: 402: 382: 243:, define the function 201:of all functions from 130: 87: 61: 1510: 1426: 1387: 1337:of functions—a 1335:pointwise convergence 1171: 1129: 1097: 1073:matrix multiplication 1066: 989: 924: 922:{\displaystyle v_{i}} 897: 877: 857: 834: 811: 809:{\displaystyle K^{n}} 776: 752: 728: 674: 603: 581: 503: 423: 403: 383: 116: 88: 62: 1539:Gierz, et al., p. 26 1449: 1396: 1345: 1138: 1106: 1086: 1001: 933: 906: 886: 866: 846: 823: 793: 765: 741: 717: 618: 592: 516: 438: 412: 392: 366: 109:Pointwise operations 95:pointwise operations 74: 60:{\displaystyle f(x)} 42: 1381: 1286:projection operator 1245:continuous lattices 1192:on functions. With 1180:Pointwise relations 862:. If we denote the 735:algebraic structure 381:{\displaystyle f+g} 138:A binary operation 18:Pointwise operation 1561:, Springer, 2005, 1505: 1467: 1421: 1382: 1361: 1298:, where id is the 1166: 1124: 1092: 1061: 984: 919: 892: 872: 852: 829: 806: 771: 747: 723: 669: 598: 576: 498: 418: 398: 378: 131: 86:{\displaystyle f.} 83: 57: 1452: 1329:An example of an 1300:identity function 1095:{\displaystyle v} 895:{\displaystyle v} 875:{\displaystyle i} 855:{\displaystyle K} 832:{\displaystyle n} 774:{\displaystyle A} 750:{\displaystyle X} 726:{\displaystyle A} 421:{\displaystyle g} 401:{\displaystyle f} 388:of two functions 134:Formal definition 16:(Redirected from 1614: 1540: 1537: 1531: 1528: 1514: 1512: 1511: 1506: 1477: 1476: 1466: 1445: 1441: 1437: 1430: 1428: 1427: 1422: 1408: 1407: 1391: 1389: 1388: 1383: 1380: 1375: 1360: 1359: 1262:closure operator 1242: 1175: 1173: 1172: 1167: 1165: 1164: 1133: 1131: 1130: 1125: 1101: 1099: 1098: 1093: 1070: 1068: 1067: 1062: 1060: 1059: 1044: 1043: 1028: 1027: 993: 991: 990: 985: 983: 982: 970: 969: 957: 956: 928: 926: 925: 920: 918: 917: 901: 899: 898: 893: 881: 879: 878: 873: 861: 859: 858: 853: 838: 836: 835: 830: 815: 813: 812: 807: 805: 804: 780: 778: 777: 772: 756: 754: 753: 748: 732: 730: 729: 724: 678: 676: 675: 670: 607: 605: 604: 599: 585: 583: 582: 577: 507: 505: 504: 499: 427: 425: 424: 419: 407: 405: 404: 399: 387: 385: 384: 379: 334: 324: 270: 242: 225: 208: 204: 200: 190: 159: 155: 92: 90: 89: 84: 66: 64: 63: 58: 34:, the qualifier 21: 1622: 1621: 1617: 1616: 1615: 1613: 1612: 1611: 1597: 1596: 1549: 1544: 1543: 1538: 1534: 1529: 1525: 1520: 1472: 1468: 1456: 1450: 1447: 1446: 1443: 1439: 1435: 1403: 1399: 1397: 1394: 1393: 1376: 1365: 1355: 1351: 1346: 1343: 1342: 1324: 1315:if and only if 1312:kernel operator 1293: 1220: 1182: 1160: 1156: 1139: 1136: 1135: 1107: 1104: 1103: 1087: 1084: 1083: 1052: 1048: 1036: 1032: 1020: 1016: 1002: 999: 998: 978: 974: 965: 961: 952: 948: 934: 931: 930: 913: 909: 907: 904: 903: 887: 884: 883: 867: 864: 863: 847: 844: 843: 824: 821: 820: 800: 796: 794: 791: 790: 787: 766: 763: 762: 742: 739: 738: 718: 715: 714: 695: 679: 619: 616: 615: 593: 590: 589: 586: 517: 514: 513: 508: 439: 436: 435: 432:is defined by: 413: 410: 409: 393: 390: 389: 367: 364: 363: 360: 336: 326: 318: 307: 292: 285: 274: 261: 254: 244: 233: 227: 216: 210: 206: 202: 192: 161: 157: 139: 136: 111: 75: 72: 71: 43: 40: 39: 28: 23: 22: 15: 12: 11: 5: 1620: 1610: 1609: 1582: 1581: 1570: 1548: 1545: 1542: 1541: 1532: 1522: 1521: 1519: 1516: 1504: 1501: 1498: 1495: 1492: 1489: 1486: 1483: 1480: 1475: 1471: 1465: 1462: 1459: 1455: 1420: 1417: 1414: 1411: 1406: 1402: 1379: 1374: 1371: 1368: 1364: 1358: 1354: 1350: 1327: 1326: 1320: 1303: 1289: 1181: 1178: 1163: 1159: 1155: 1152: 1149: 1146: 1143: 1123: 1120: 1117: 1114: 1111: 1091: 1058: 1055: 1051: 1047: 1042: 1039: 1035: 1031: 1026: 1023: 1019: 1015: 1012: 1009: 1006: 981: 977: 973: 968: 964: 960: 955: 951: 947: 944: 941: 938: 916: 912: 891: 871: 851: 828: 818:natural number 803: 799: 786: 783: 770: 746: 722: 707:distributivity 694: 691: 668: 665: 662: 659: 656: 653: 650: 647: 644: 641: 638: 635: 632: 629: 626: 623: 614: 597: 575: 572: 569: 566: 563: 560: 557: 554: 551: 548: 545: 542: 539: 536: 533: 530: 527: 524: 521: 512: 497: 494: 491: 488: 485: 482: 479: 476: 473: 470: 467: 464: 461: 458: 455: 452: 449: 446: 443: 434: 417: 397: 377: 374: 371: 359: 356: 316: 305: 290: 283: 273: 259: 252: 231: 214: 135: 132: 110: 107: 82: 79: 56: 53: 50: 47: 26: 9: 6: 4: 3: 2: 1619: 1608: 1605: 1604: 1602: 1595: 1594: 1592: 1588: 1579: 1575: 1571: 1568: 1567:1-85233-905-5 1564: 1560: 1557:T. S. Blyth, 1556: 1555: 1554: 1553: 1536: 1527: 1523: 1515: 1502: 1496: 1490: 1487: 1481: 1473: 1469: 1457: 1433: 1418: 1412: 1409: 1404: 1400: 1372: 1369: 1366: 1356: 1352: 1341:of functions 1340: 1336: 1332: 1323: 1318: 1314: 1313: 1308: 1304: 1301: 1297: 1292: 1287: 1283: 1279: 1275: 1271: 1267: 1264: 1263: 1258: 1257: 1256: 1254: 1250: 1246: 1240: 1236: 1232: 1228: 1224: 1218: 1214: 1210: 1206: 1202: 1199: 1195: 1191: 1190:partial order 1187: 1177: 1161: 1157: 1153: 1147: 1141: 1121: 1115: 1112: 1109: 1089: 1081: 1076: 1074: 1056: 1053: 1049: 1045: 1040: 1037: 1033: 1029: 1024: 1021: 1013: 1010: 1007: 995: 979: 975: 971: 966: 962: 958: 953: 945: 942: 939: 914: 910: 889: 869: 849: 842: 826: 819: 801: 797: 782: 768: 760: 744: 736: 720: 712: 708: 704: 703:commutativity 700: 699:associativity 690: 688: 685:pointwise is 684: 666: 660: 654: 651: 648: 645: 639: 630: 627: 624: 613: 611: 595: 573: 567: 561: 558: 552: 546: 543: 537: 528: 525: 522: 511: 495: 489: 483: 480: 474: 468: 465: 459: 450: 447: 444: 433: 431: 415: 395: 375: 372: 369: 355: 353: 349: 345: 341: 333: 329: 322: 315: 311: 304: 300: 296: 289: 282: 278: 272: 269: 265: 258: 251: 247: 241: 237: 230: 224: 220: 213: 199: 195: 188: 184: 180: 176: 172: 168: 164: 154: 150: 146: 142: 128: 124: 120: 115: 106: 104: 100: 96: 80: 77: 70: 51: 45: 37: 33: 19: 1584: 1583: 1577: 1558: 1551: 1550: 1535: 1526: 1438:if for each 1328: 1321: 1316: 1310: 1309:is called a 1306: 1295: 1290: 1281: 1280:self-map on 1269: 1265: 1260: 1252: 1248: 1238: 1234: 1230: 1226: 1222: 1216: 1212: 1208: 1204: 1197: 1193: 1186:order theory 1183: 1077: 996: 788: 696: 682: 680: 587: 509: 361: 347: 343: 339: 337: 331: 327: 320: 313: 309: 302: 298: 294: 287: 280: 276: 267: 263: 256: 249: 245: 239: 235: 228: 222: 218: 211: 197: 193: 186: 182: 178: 174: 170: 166: 162: 152: 148: 144: 140: 137: 126: 94: 35: 29: 1574:D. S. Scott 1268:on a poset 759:carrier set 687:convolution 191:on the set 32:mathematics 1587:PlanetMath 1547:References 1331:infinitary 1278:idempotent 1134:such that 693:Properties 338:Commonly, 1464:∞ 1461:→ 1432:converges 1416:⟶ 1378:∞ 1119:→ 839:and some 816:for some 652:⋅ 649:λ 628:⋅ 625:λ 596:λ 559:⋅ 526:⋅ 156:on a set 103:relations 36:pointwise 1601:Category 1339:sequence 1284:(i.e. a 1274:monotone 1075:is not. 733:is some 711:codomain 430:codomain 358:Examples 325:for all 69:function 67:of some 757:to the 1565:  1201:posets 713:. If 610:scalar 99:domain 1518:Notes 1392:with 1272:is a 1225:∈ A) 1080:tuple 841:field 608:is a 352:arity 181:) → ( 173:) × ( 1563:ISBN 1319:≤ id 1276:and 1233:) ≤ 705:and 408:and 342:and 297:) = 226:and 129:=2π. 1454:lim 1442:in 1219:if 1184:In 902:as 761:of 683:not 312:), 293:))( 271:by 262:): 205:to 165:: ( 119:sin 30:In 1603:: 1576:: 1294:≤ 1259:A 1251:→ 1221:(∀ 1215:≤ 1207:→ 1196:, 1078:A 994:. 701:, 689:. 612:: 354:. 330:∈ 323:)) 286:, 266:→ 255:, 238:→ 234:: 221:→ 217:: 196:→ 151:→ 147:× 143:: 123:ln 1593:. 1569:. 1503:. 1500:) 1497:x 1494:( 1491:f 1488:= 1485:) 1482:x 1479:( 1474:n 1470:f 1458:n 1444:X 1440:x 1436:f 1419:Y 1413:X 1410:: 1405:n 1401:f 1373:1 1370:= 1367:n 1363:) 1357:n 1353:f 1349:( 1325:. 1322:A 1317:k 1307:k 1302:. 1296:c 1291:A 1282:P 1270:P 1266:c 1253:B 1249:A 1241:) 1239:x 1237:( 1235:g 1231:x 1229:( 1227:f 1223:x 1217:g 1213:f 1209:B 1205:A 1198:B 1194:A 1162:i 1158:v 1154:= 1151:) 1148:i 1145:( 1142:f 1122:K 1116:n 1113:: 1110:f 1090:v 1057:j 1054:i 1050:B 1046:+ 1041:j 1038:i 1034:A 1030:= 1025:j 1022:i 1018:) 1014:B 1011:+ 1008:A 1005:( 980:i 976:v 972:+ 967:i 963:u 959:= 954:i 950:) 946:v 943:+ 940:u 937:( 915:i 911:v 890:v 870:i 850:K 827:n 802:n 798:K 769:A 745:X 721:A 667:. 664:) 661:x 658:( 655:f 646:= 643:) 640:x 637:( 634:) 631:f 622:( 574:. 571:) 568:x 565:( 562:g 556:) 553:x 550:( 547:f 544:= 541:) 538:x 535:( 532:) 529:g 523:f 520:( 496:. 493:) 490:x 487:( 484:g 481:+ 478:) 475:x 472:( 469:f 466:= 463:) 460:x 457:( 454:) 451:g 448:+ 445:f 442:( 416:g 396:f 376:g 373:+ 370:f 348:o 344:O 340:o 335:. 332:X 328:x 321:x 319:( 317:2 314:f 310:x 308:( 306:1 303:f 301:( 299:o 295:x 291:2 288:f 284:1 281:f 279:( 277:O 275:( 268:Y 264:X 260:2 257:f 253:1 250:f 248:( 246:O 240:Y 236:X 232:2 229:f 223:Y 219:X 215:1 212:f 207:Y 203:X 198:Y 194:X 189:) 187:Y 185:→ 183:X 179:Y 177:→ 175:X 171:Y 169:→ 167:X 163:O 158:Y 153:Y 149:Y 145:Y 141:o 127:x 81:. 78:f 55:) 52:x 49:( 46:f 20:)

Index

Pointwise operation
mathematics
function
domain
relations

sin
ln
arity
codomain
scalar
convolution
associativity
commutativity
distributivity
codomain
algebraic structure
carrier set
natural number
field
matrix multiplication
tuple
order theory
partial order
posets
continuous lattices
closure operator
monotone
idempotent
projection operator

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