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Modes of convergence

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187:), which in turn implies absolute convergence of some grouping (not reordering). The sequence of partial sums obtained by grouping is a subsequence of the partial sums of the original series. The convergence of each absolutely convergent series is an equivalent condition for a normed vector space to be 251:
Pointwise convergence implies pointwise Cauchy convergence, and the converse holds if the space in which the functions take their values is complete. Uniform convergence implies pointwise convergence and uniform Cauchy convergence. Uniform Cauchy convergence and pointwise convergence of a subsequence
282:(even in the weakest sense: every point has compact neighborhood), then local uniform convergence is equivalent to compact (uniform) convergence. Roughly speaking, this is because "local" and "compact" connote the same thing. 194:
Absolute convergence and convergence together imply unconditional convergence, but unconditional convergence does not imply absolute convergence in general, even if the space is Banach, although the implication holds in
271:) may be defined. "Compact convergence" is always short for "compact uniform convergence," since "compact pointwise convergence" would mean the same thing as "pointwise convergence" (points are always compact). 240:. It is defined as convergence of the sequence of values of the functions at every point. If the functions take their values in a uniform space, then one can define pointwise Cauchy convergence, 479:, then several modes of convergence that depend on measure-theoretic, rather than solely topological properties, arise. This includes pointwise convergence almost-everywhere, convergence in 222: 425: 375: 335: 181: 108:
are spaces in which Cauchy filters may be defined. Convergence implies "Cauchy convergence", and Cauchy convergence, together with the existence of a convergent
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is said to be convergent. This article describes various modes (senses or species) of convergence in the settings where they are defined. For a list of
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Uniform convergence implies both local uniform convergence and compact convergence, since both are local notions while uniform convergence is global. If
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imply uniform convergence of the sequence, and if the codomain is complete, then uniform Cauchy convergence implies uniform convergence.
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The most basic type of convergence for a sequence of functions (in particular, it does not assume any topological structure on the
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Pointwise and uniform convergence of series of functions are defined in terms of convergence of the sequence of partial sums.
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in terms of the partial sums of the series. If, in addition, the functions take values in a normed linear space, then
431:, pointwise absolute convergence implies pointwise convergence, and normal convergence implies uniform convergence. 435: 256: 245: 133: 125: 54: 457:
Normal convergence implies both local normal convergence and compact normal convergence. And if the domain is
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is defined as convergence of the sequence of partial sums. An important concept when considering series is
237: 113: 82: 198: 233: 140: 129: 28: 390: 340: 300: 146: 508: 502: 476: 439: 294: 264: 241: 184: 90: 78: 58: 484: 447: 443: 380: 136:, which guarantees that the limit of the series is invariant under permutations of the summands. 46: 461:(even in the weakest sense), then local normal convergence implies compact normal convergence. 541: 520: 505: – Use of filters to describe and characterize all basic topological notions and results. 297:, absolute convergence refers to convergence of the series of positive, real-valued functions 86: 42: 62: 499: – Notions of probabilistic convergence, applied to estimation and asymptotic analysis 255:
If the domain of the functions is a topological space and the codomain is a uniform space,
183:). Absolute convergence implies Cauchy convergence of the sequence of partial sums (by the 89:
are a generalization of sequences that are useful in spaces which are not first countable.
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of metric spaces, and its generalizations is defined in terms of Cauchy sequences.
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is convergence of the series of non-negative real numbers obtained by taking the
451: 109: 20: 337:. "Pointwise absolute convergence" is then simply pointwise convergence of 41:
Each of the following objects is a special case of the types preceding it:
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For functions defined on a topological space, one can define (as above)
483:-mean and convergence in measure. These are of particular interest in 228:
Convergence of sequence of functions on a topological space
517: – Annotated index of various modes of convergence 387:
of each function in the series (uniform convergence of
393: 343: 303: 201: 149: 419: 369: 329: 286:Series of functions on a topological abelian group 216: 175: 511: – Value to which tends an infinite sequence 120:Series of elements in a topological abelian group 100:. Cauchy nets and filters are generalizations to 523: – A generalization of a sequence of points 93:further generalize the concept of convergence. 8: 446:(local, uniform, absolute convergence) and 65:, and the real/complex numbers. Also, any 412: 406: 397: 392: 362: 356: 347: 342: 322: 316: 307: 302: 208: 204: 203: 200: 168: 162: 153: 148: 139:In a normed vector space, one can define 77:Convergence can be defined in terms of 515:Modes of convergence (annotated index) 37:Modes of convergence (annotated index) 7: 465:Functions defined on a measure space 112:implies convergence. The concept of 527:Topologies on spaces of linear maps 23:, there are many senses in which a 394: 344: 304: 150: 14: 293:For functions taking values in a 267:(i.e. uniform convergence on all 96:In metric spaces, one can define 217:{\displaystyle \mathbb {R} ^{d}} 16:Property of a sequence or series 497:Convergence of random variables 471:Convergence of random variables 259:(i.e. uniform convergence on a 73:Elements of a topological space 475:If one considers sequences of 420:{\displaystyle \Sigma |g_{k}|} 413: 398: 370:{\displaystyle \Sigma |g_{k}|} 363: 348: 330:{\displaystyle \Sigma |g_{k}|} 323: 308: 176:{\displaystyle \Sigma |b_{k}|} 169: 154: 143:as convergence of the series ( 1: 440:compact (uniform) convergence 265:compact (uniform) convergence 563: 468: 448:compact normal convergence 246:uniform Cauchy convergence 547:Convergence (mathematics) 450:(absolute convergence on 436:local uniform convergence 385:uniform (i.e. "sup") norm 257:local uniform convergence 134:unconditional convergence 126:topological abelian group 55:topological abelian group 444:local normal convergence 104:. Even more generally, 421: 371: 331: 218: 177: 83:first-countable spaces 422: 372: 332: 238:pointwise convergence 236:of the functions) is 219: 178: 477:measurable functions 391: 341: 301: 199: 147: 141:absolute convergence 69:is a uniform space. 33:modes of convergence 509:Limit of a sequence 503:Filters in topology 295:normed linear space 263:of each point) and 242:uniform convergence 185:triangle inequality 128:, convergence of a 485:probability theory 454:) can be defined. 417: 381:Normal convergence 367: 327: 214: 191:(i.e.: complete). 173: 47:topological spaces 521:Net (mathematics) 248:of the sequence. 554: 426: 424: 423: 418: 416: 411: 410: 401: 376: 374: 373: 368: 366: 361: 360: 351: 336: 334: 333: 328: 326: 321: 320: 311: 223: 221: 220: 215: 213: 212: 207: 182: 180: 179: 174: 172: 167: 166: 157: 98:Cauchy sequences 63:Euclidean spaces 562: 561: 557: 556: 555: 553: 552: 551: 532: 531: 493: 473: 467: 459:locally compact 402: 389: 388: 352: 339: 338: 312: 299: 298: 288: 280:locally compact 269:compact subsets 230: 202: 197: 196: 158: 145: 144: 122: 75: 17: 12: 11: 5: 560: 558: 550: 549: 544: 534: 533: 530: 529: 524: 518: 512: 506: 500: 492: 489: 469:Main article: 466: 463: 415: 409: 405: 400: 396: 365: 359: 355: 350: 346: 325: 319: 315: 310: 306: 287: 284: 229: 226: 211: 206: 171: 165: 161: 156: 152: 121: 118: 102:uniform spaces 74: 71: 51:uniform spaces 15: 13: 10: 9: 6: 4: 3: 2: 559: 548: 545: 543: 540: 539: 537: 528: 525: 522: 519: 516: 513: 510: 507: 504: 501: 498: 495: 494: 490: 488: 486: 482: 478: 472: 464: 462: 460: 455: 453: 449: 445: 441: 437: 432: 430: 429:Banach spaces 407: 403: 386: 382: 378: 357: 353: 317: 313: 296: 291: 285: 283: 281: 277: 272: 270: 266: 262: 258: 253: 249: 247: 243: 239: 235: 227: 225: 209: 192: 190: 186: 163: 159: 142: 137: 135: 131: 127: 119: 117: 115: 111: 107: 106:Cauchy spaces 103: 99: 94: 92: 88: 84: 80: 72: 70: 68: 64: 60: 59:normed spaces 56: 52: 48: 44: 39: 38: 34: 30: 26: 22: 480: 474: 456: 452:compact sets 433: 379: 292: 289: 275: 273: 261:neighborhood 254: 250: 231: 193: 138: 123: 114:completeness 95: 76: 67:metric space 40: 32: 18: 110:subsequence 21:mathematics 536:Categories 395:Σ 345:Σ 305:Σ 151:Σ 79:sequences 542:Topology 491:See also 25:sequence 91:Filters 427:). In 244:, and 234:domain 189:Banach 130:series 35:, see 29:series 124:In a 27:or a 438:and 87:Nets 43:sets 278:is 81:in 19:In 538:: 487:. 377:. 224:. 85:. 61:, 57:, 53:, 49:, 45:, 481:p 414:| 408:k 404:g 399:| 364:| 358:k 354:g 349:| 324:| 318:k 314:g 309:| 276:X 210:d 205:R 170:| 164:k 160:b 155:|

Index

mathematics
sequence
series
Modes of convergence (annotated index)
sets
topological spaces
uniform spaces
topological abelian group
normed spaces
Euclidean spaces
metric space
sequences
first-countable spaces
Nets
Filters
Cauchy sequences
uniform spaces
Cauchy spaces
subsequence
completeness
topological abelian group
series
unconditional convergence
absolute convergence
triangle inequality
Banach
domain
pointwise convergence
uniform convergence
uniform Cauchy convergence

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