---
New features:
- `LinearModelFit` 592
- `EasterSunday` 590
- `DSolve` for PDE 589
- `LogisticSigmoid` 588
- `CentralMoment`, `Skewness`, `Kurtosis` 583
- New web interface 574
- `Image` support and image processing functions 571, 541, 497, 493, 482
- `StringCases`, `Shortest`, `Longest` string match/replace 570
- `Quantime` and `Quartiles` 567
- `Pick` 563
- `ByteCount` 560
- `Nearest` 559
- `Count` 558
- `RegularPolygon` 556
- impoved date parsing 555
- `Permutations` 552
- LLVM compilation of simple expressions 548
- `NumberForm` 534, 530, 455
- basic scripting with matihcsscript
- Arcs for `Disk` and `Circle` 498, 526
- download from URL 525
- `$CommandLine` 524
- `Background` option for `Graphics` 522
- `Style` 521, 471, 468
- abbreviated string patterns 518
- `Return` 515
- better messages 514
- Undo and redo functionality in web interface 511
- `Covariance` and `Correlation` 506
- `ToLowerCase`, `ToUpperCase`, `LowerCaseQ`, `UpperCaseQ` 505
- `StringRepeat` 504
- `TextRecognise` 500
- axis numbers to integers when possible 495
- `PointSize` 494
- `FilledCurve`, `BezierCurve`, `BezierFunction` 485
- `PadLeft`, `PadRight` 484
- `Manipulate` 483, 379, 366
- `Replace` 478
- String operator versions 476
- improvements to `Piecewise` 475
- Derivation typo 474
- Natural language processing functions 472
- `Arrow`, `Arrowheads` 470
- optional modules with requires attribute 465
- `MachinePrecision` 463
- `Catenate` 454
- `Quotient` 456
- disable spellcheck on query fields 453
- `MapThread` 452
- `Scan` and `Return` 451
- `On` and `Off` 450
- `$MachineEpsilon` and `$MachinePrecision` 449
- `ExpandAll` 447
- `Position` 445
- `StringPosition` 444
- `AppendTo`, `DeleteCases`, `TrueQ`, `ValueQ` 443
- `Indeterminate` 439
- more integral functions 437
- `ExpIntegralEi` and `ExpIntegralE` 435
- `Variance` and `StandardDeviation` 424
- Legacy `Random` function 422
- Improved gamma functions 419
- new recursive descent parser 416
- `TakeSmallest` and related 412
- `Boole` 411
- `Median`, `RankedMin`, `RankedMax` 410
- `HammingDistance` 409
- `JaccardDissimilarity` and others 407
- `EuclideanDistance` and related 405
- Magic methods for `Expression` 404
- `Reverse` 403
- `RotateLeft` and `RotateRight` 402
- `ColorDistance`, `ColorConvert` 400
- Predefine and document `$Aborted` and `$Failed` 399
- `IntegerString`, `FromDigits`, and more 397
- `EditDistance` and `DamerauLevenshteinDistance` 394
- `QRDecomposition` 393
- `RandomChoice` and `RandomSample` 488
- `Hash` 387
- Graphics boxes for colors 386
- `Except` 353
- Document many things 341
- `StringExpression` 339
- Legacy file functions 338
- upgrade to Sympy 1.0 334
Bug fixes:
- Nested `Module`s 591, 584
- Python2 Import bug 565
- XML import 554
- `\[Minus]` parsing bug 550
- `Cases` evaluation bug 531
- `Take` edge cases 519
- `PlotSize` bug 512
- Firefox nodeValue warning 496
- Django database permissions 489
- `FromDigits` missing message 479
- numerfication upon result only 477
- saving and loading notebooks 473
- `Rationalise` 460
- `Optional` and `Pattern` precedence values 459
- fix `Sum[i / Log[i], {i, 1, Infinity}]` 442
- added `\[Pi]`, `\[Degree]`, `\[Infinity]` and `\[I]` to parser 441
- fix loss of precision bugs 440
- many minor bugs from fuzzing 436
- `Positive`/`Negative` do not numerify arguments 430 fixes 380
- chains of approximate identites 429
- Logical expressions behave inconsistently/incorrectly 420 fixes 260
- fix `Take[_Symbol, ___]` 396
- avoid slots in rule handling 375 fixes 373
- `Gather`, `GatherBy`, `Tally`, `Union`, `Intersect`, `IntersectingQ`, `DisjointQ`, `SortBy` and `BinarySearch` 373
- symbol string comparison bug 371
- Fix `Begin`/`BeginPackage` leaking user-visible symbols 352
- Fix `TableForm` and `Dimensions` with an empty list 343
- Trailing slash bug 337
- Global system bug 336
- `Null` comparison bug 371
- `CompoundExpression` `Out[n]` assignment bug 335 fixes 331
- load unevaluated cells 332
Performance improvements:
- Large expression formatting with `$OutputSizeLimit` 581
- Faster terminal output 579
- faster `walk_paths` 578
- faster flatten for `Sequence` symbols 577
- compilation for plotting 576
- `Sequence` optimisations 568
- Improvements to `GatherBy` 566
- optimised `Expression` creation 536
- `Expression` caching 535
- `Definitions` caching 507
- optimised `Position`, `Cases`, `DeleteCases` 503
- optimised `StringSplit` 502
- optimised `$RecursionLimit` 501
- optimised insert_rule 464
- optimised `IntegerLength` 462
- optimised `BaseExpression` creation 458
- No reevaluation of evaluated values 391
- shortcut rule lookup 389
- 15% performance boost by preventing some rule lookups 384
- 25% performance boost using same over `__eq__`
- n log n algorithm for `Complement` and `DeleteDuplicates` 373
- Avoid computing `x^y` in `PowerMod[x, y, m]` 342