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Talk:Cycle notation

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321:(3) The use of the term orbits here and in the article is at best obscure and certainly not conventional in the sense of popular usage. The mathematical structure of an orbit and how an orbit is generated by a group action are in no way similar to the structure and generation implied by the usage of the term here. This usage should not be promoted in general and it should not be repeated here as it only leads to confusion (despite the fact that at least one mathematics book, as cited above, has been published stipulating this usage). The term orbits as used in the article should be replaced with a descriptive phrase such as collections of cycle elements (referring to the elements used in the denotation of a cyclic permutation). 318:(2) The use of the term orbits in this phrase is circular in its use as a means of defining the word orbit. Also, it never describes how a cyclic group (presumed to mean not a group of, but a simple collection of cyclic permutations) is related to its orbits. Here, the use of the term orbit is probably intended to refer to the orbit for a cyclic permutation, which in turn is intended to mean the collection of elements listed in the denotation of the cyclic permutation when the permutation is denoted in cycle notation. 84: 74: 53: 22: 315:(1) What is cyclic group? How is it generated? It may be that the intended meaning is the reverse. It is known that any permutation is generated by a product of cyclic permutations. The collection of cyclic permutations that generate a given permutation, however does not necessarily form a group. The phrase would then become "orbits of the collection of cyclic permutations which generate that permutation." 255:
The orbits of a single permutation are the same as the orbits of the cyclic group generated by that permutation. The orbits of (1,2,3)(4,5)(6)(7) = (1,2,3)(4,5) = on {1,2,3,4,5,6,7} are {1,2,3}, {4,5}, {6}, and {7}. If you omit 1-cycles, then you must be explicit about the domain being acted on.
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Seems O(n) to me: you start with the first element, compute the output of the permutation, and use that as input. If the output is the first element again, you start over with another unused element, the used elements are one cycle. Each element of the permutation will be used exactly once, and the
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Do not agree. This usage and definition of the term orbit should not be included on the Knowledge page defining orbit. It is unconventional and completely different from the common and proper usage of the
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Thanks for answering Jack! Perhaps we should include this definition in that of orbit? In most places, this is not mentioned, but I finally came across a book by Gerhard Michler which gave this definition.
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which is what the definition is trying to say. The author of the article probably thought that the concept of a cyclic group generated by an element would be understood by readers of this page.
140: 438:) is {1,2,3}, the orbit of 4 is {4,5}, the orbit of 6 is {6} and so on. Notice how the elements in an orbit are precisely the elements in a cycle of the original permutation 464:
This article omits motivation and barely has examples. At the very least, it should explain how group multiplication works for cycles. Moly 15:58, 23 October 2012 (UTC)
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cycles will be disjoint (this is the exact technique used to prove the theorem). I don't think it'd be possible to do in a better time.
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Jack was quite correct and the use of the term orbit in this article is quite standard and in agreement with the article
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on Knowledge. If you would like to participate, please visit the project page, where you can join
447: 279: 241: 166: 89: 356:. Perhaps Jack's explanation should be fleshed out and given in this article. Given any element 73: 52: 231:
acts upon, but not of the group element itself. Can someone please clarify in what context is
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What is the algorithmic complexity of decomposing a permutation into those cycles?
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permutation is being concerned, then should any element not have only one orbit?
102: 79: 472: 312:"orbits of the cyclic group generated by that permutation" is not clear. 451: 336: 287: 265: 249: 174: 353: 389:, etc. when the group is finite and written multiplicatively. If 15: 401:), then this subgroup acts naturally on the set {1,2,..., 217: 197: 101:, a collaborative effort to improve the coverage of 223: 203: 8: 191:defines the orbit of an element of the set 433:. The orbit of 1 under this subgroup (< 322: 47: 216: 196: 32:does not require a rating on Knowledge's 49: 95:This redirect is within the scope of 19: 7: 498:Redirect-Class mathematics articles 38:It is of interest to the following 14: 503:Low-priority mathematics articles 115:Knowledge:WikiProject Mathematics 373:) is the subgroup consisting of 364:, the cyclic group generated by 183:permutation as a group of cycles 135:This redirect has been rated as 118:Template:WikiProject Mathematics 82: 72: 51: 20: 1: 452:23:52, 30 December 2014 (UTC) 337:21:44, 30 December 2014 (UTC) 235:being used here? Also, since 109:and see a list of open tasks. 175:13:32, 1 January 2011 (UTC) 165:You should sign your name. 519: 409:=(123)(45)(6)(7), we have 429:=(1)(2)(3)(4)(5)(6)(7) = 405:}. Using Jack's example, 393:is the permutation group 288:00:36, 3 March 2011 (UTC) 266:15:20, 2 March 2011 (UTC) 250:06:39, 2 March 2011 (UTC) 134: 67: 46: 368:(usually denoted by < 141:project's priority scale 98:WikiProject Mathematics 417:=(1)(2)(3)(45)(6)(7), 225: 205: 187:The Knowledge page on 425:=(132)(45)(6)(7) and 413:= (132)(4)(5)(6)(7), 226: 206: 421:=(123)(4)(5)(6)(7), 215: 195: 121:mathematics articles 221: 201: 90:Mathematics portal 34:content assessment 485: 471:comment added by 339: 327:comment added by 286: 248: 224:{\displaystyle G} 211:on which a group 204:{\displaystyle S} 155: 154: 151: 150: 147: 146: 510: 484: 465: 444:Bill Cherowitzo 285: 282: 247: 244: 230: 228: 227: 222: 210: 208: 207: 202: 123: 122: 119: 116: 113: 92: 87: 86: 76: 69: 68: 63: 55: 48: 25: 24: 16: 518: 517: 513: 512: 511: 509: 508: 507: 488: 487: 466: 280: 242: 213: 212: 193: 192: 185: 120: 117: 114: 111: 110: 88: 81: 61: 12: 11: 5: 516: 514: 506: 505: 500: 490: 489: 463: 461: 460: 459: 458: 457: 456: 455: 454: 343: 342: 341: 340: 319: 316: 313: 307: 306: 305: 304: 303: 302: 293: 292: 291: 290: 271: 269: 268: 220: 200: 184: 181: 180: 179: 178: 177: 153: 152: 149: 148: 145: 144: 133: 127: 126: 124: 107:the discussion 94: 93: 77: 65: 64: 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 515: 504: 501: 499: 496: 495: 493: 486: 482: 478: 474: 470: 453: 449: 445: 441: 436: 432: 428: 424: 420: 416: 412: 408: 404: 400: 396: 392: 388: 384: 380: 376: 371: 367: 363: 360:of any group 359: 355: 351: 350: 349: 348: 347: 346: 345: 344: 338: 334: 330: 326: 320: 317: 314: 311: 310: 309: 308: 299: 298: 297: 296: 295: 294: 289: 284: 283: 281:Pratik.Mallya 276: 275: 274: 273: 272: 267: 263: 259: 254: 253: 252: 251: 246: 245: 243:Pratik.Mallya 238: 234: 218: 198: 190: 182: 176: 172: 168: 164: 163: 160: 159: 158: 142: 138: 132: 129: 128: 125: 108: 104: 100: 99: 91: 85: 80: 78: 75: 71: 70: 66: 60: 57: 54: 50: 45: 41: 35: 31: 27: 23: 18: 17: 467:— Preceding 462: 439: 434: 430: 426: 422: 418: 414: 410: 406: 402: 398: 394: 390: 386: 382: 378: 374: 369: 365: 361: 357: 323:— Preceding 278: 270: 240: 236: 232: 186: 156: 137:Low-priority 136: 96: 62:Low‑priority 40:WikiProjects 29: 258:JackSchmidt 112:Mathematics 103:mathematics 59:Mathematics 492:Categories 329:66.194.2.9 481:contribs 469:unsigned 325:unsigned 30:redirect 139:on the 189:orbits 167:Zyszys 36:scale. 437:: --> 372:: --> 354:orbit 301:term. 233:orbit 28:This 477:talk 473:Moly 448:talk 333:talk 262:talk 171:talk 237:one 131:Low 494:: 483:) 479:• 450:) 385:, 381:, 377:, 335:) 264:) 173:) 475:( 446:( 440:g 435:g 431:e 427:g 423:g 419:g 415:g 411:g 407:g 403:n 399:n 397:( 395:S 391:G 387:g 383:g 379:g 375:e 370:g 366:g 362:G 358:g 331:( 260:( 219:G 199:S 169:( 143:. 42::

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13:32, 1 January 2011 (UTC)
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06:39, 2 March 2011 (UTC)
JackSchmidt
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15:20, 2 March 2011 (UTC)
Pratik.Mallya
00:36, 3 March 2011 (UTC)
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21:44, 30 December 2014 (UTC)
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Bill Cherowitzo

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