Questions on undocumented functionality of Mathematica. Note that such functions might be subject to change without notice in future versions.

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2
votes
0answers
56 views

Undocumented function SumOfSquaresReps

There is an interesting (and documented) number-theoretic function in MMA called PowersRepresentations[$n$, $k$, $p$]. It gives the distinct representations of the integer $n$ as a sum of $k$ ...
2
votes
1answer
84 views

What Method values are available for Plot?

The Documentation Center article on Plot notes under Details and Options that Method is one of the options for ...
14
votes
0answers
148 views

Undocumented fourth parameter of Collect; how long has it been there?

While tinkering with How to get a list of monomials of a polynomial without coefficients? on a whim I tried a fourth argument in Collect and found: ...
11
votes
2answers
192 views

What will happen if I set ExclusionsStyle for points in 2D plot?

For example f[x_] := (x^5 - 4 x^2 + 1)/(x - 1/2); Plot[f[x], {x, -1, 2}, Exclusions -> {f[x] == 0}, ExclusionsStyle -> Dashed] Has the ...
13
votes
1answer
135 views

How to retrieve current FaceForm?

The current colour in a Graphics object can be retrieved using CurrentValue["Color"] for use in Dynamic stuff. Example: ...
5
votes
1answer
63 views

Can Someone Please Explain Internal`$SameQTolerance?

If I input Internal`$SameQTolerance (* output = 0.30103 *) which is the approximation of Log[10,2], or ...
12
votes
1answer
163 views

Is there a way to control which special forms Normal converts?

Normal documentation reads: Normal[expr] converts expr to a normal expression, from a variety of special forms. But is there a way to control which special ...
10
votes
1answer
235 views

How can I make FilledCurve smoother?

In How can I generate and randomly assign color to annular sectors? J.M. showed an interesting way to create a sector graphic using FilledCurve. Unfortunately it ...
8
votes
1answer
127 views

What's the goal of the Macros` package?

I see in the Mathematica install a Macros` package. In windows the paths is for example: ...
8
votes
1answer
178 views

Possible Method for MatrixExp

Well, probably a hard question, but I think it's better to cry out loud :). I noticed that MatrixExp owns Method option when ...
18
votes
1answer
399 views

What are SparseArray Properties? How and when should they be used?

A strange undocumented form of SparseArray is increasingly used in answers on this site: ...
18
votes
1answer
305 views

In 10.1.0 BenchmarkPlot doesn't work?

Bug introduced in 10.1 and fixed in 10.2.0 In Mathematica 10.1.0 BenchmarkPlot from the GeneralUtilities package doesn't work; copying Taliesin Beynon's initial ...
1
vote
0answers
33 views

Understanding HoldSequence and ReleaseHoldSequence in Error Handling

I was playing with GeneralUtilities`PrintDefinitions in V10.1, and find some of native Mathematica functions using ...
24
votes
0answers
332 views

Documentation of the frequently-used functions in the context of Internal` and Compile` [duplicate]

In this site, I have gradually found out that there is a collection of functions in all kinds of answers. For instance, Compile`GetElement, ...
10
votes
1answer
165 views

Enigmatic message about MaxBend

Referring to the method I proposed for Problem with ParametricPlot Mathematica 10.0.2 throws an enigmatic error message: ...
10
votes
2answers
183 views

Why is a symbol still found after changing its context?

It seems that we can change the context of symbols: In[1]:= x = 1 Out[1]= 1 In[2]:= Context[x] = "foo`"; But then x is still ...
3
votes
0answers
49 views

Undocumented options for “BalloonEmbedding” in GraphLayout

From an error message, I see some options of the BalloonEmbedding method for GraphLayout: ...
4
votes
1answer
86 views

What are all the Properties that ColorData supports?

The documentation for ColorData reads: Possible properties in ColorData["scheme","property"] include: ...
9
votes
2answers
274 views

What does IndexBy do and how exactly does it work?

I just saw the function IndexBy in the autocomplete suggestions and I was curious to know exactly how it works. Unfortunately, there's no trace of it in the ...
17
votes
1answer
189 views

Reading from a socket stream

I noticed an undocumented socket package (SocketLink) in Mathematica (Using version 10, not sure when it was actually added) and wrote a barebones HTTP responder ...
4
votes
2answers
167 views

Is there a build-in function converting a quantity to one with mixed units (such as feet and inches)?

For example, I want to convert 179 centimeters into 5 feet and 10.4724 inches instead of 70.4724 inches (as this website did). Maybe in the future I would need to convert days to {years, months, days} ...
15
votes
2answers
313 views

What is the purpose of Internal`LocalizedBlock?

I have come across the (internal) use of of the function: Internal`LocalizedBlock I am trying to determine its purpose. It seem to behave like ...
2
votes
1answer
56 views

When is are these additional docked cell styles used?

The the style "DockedCell" is automatically used for Docked Cells even when no Cell style is specified. In the section of ...
3
votes
0answers
61 views

Lists for built-in functions that can work without brackets

I just noticed that Exit and Quit can work without brackets i.e. a single Exit or ...
6
votes
1answer
136 views

What are the arguments supplied to ColorFunction in MandelbrotSetPlot?

On the document of MandelbrotSetPlot, it said: With ColorFunction->f, where f is a function, the argument of f is a real number in proportional to the number of ...
6
votes
2answers
162 views

Finding out all undocumented values for “Properties” in XxxData[] functions

No, XxxData[] is not a new function in Mathematica 11. I am just using that name for all curated data-related functions. As you know, ...
1
vote
1answer
70 views

In which version was this Extract syntax introduced?

In Mathematica 10.0.1 this works: Extract[{a, b, c, d, e}, {{{1, 3}}, {{5, 4}}, {{2}}}] {{a, c}, {e, d}, {b}} In ...
5
votes
1answer
105 views

RawArray crashes the kernel

fixed in 10.0.2 RawArray seems to crash the kernel on my machine RawArray["Byte", {}] Is this a bug? Any insights why this happens? My system: version 10.01 ...
12
votes
2answers
179 views

Listable functions thread over Associations; is this documented?

Thanks to a somewhat misapplied use of MapThread I learned of this behavior: ...
2
votes
1answer
81 views

How to obtain a complete list of WordData's “Properties”?

Command WordData["Word", "Properties"] seems to return an endless list of properties, such as: "Definitions", ...
4
votes
1answer
141 views

Undocumented overload for Graph?

I stumbled (here, in the expression for the block diagram) upon a version of Graph that I don't see in the documentation over here. That documentation admits three overloads (the following are in my ...
5
votes
0answers
57 views

Is “MaxMessageCount” broken or is its function counter-intuitive?

Behavior remains unchanged through Mathematica version 10.1.0 As noted by kguler the Front End option: MessageOptions -> "MaxMessageCount" does not appear to ...
22
votes
2answers
595 views

Specifying non-conflicting PlotTheme options

A bug or limitation in 10.0.0 affects a few of these examples; it was resolved in 10.1.0. I am trying out Mathematica 10 on https://programming.wolframcloud.com. ...
8
votes
0answers
200 views

TableView displays negative numbers incorrectly

I'm trying to substitute TableForm with TableView because TableView is more handy with big data . But on my Mathematica 9.0.1 (ubuntu 14.04_64bit) there is a problem with negative numbers: ...
24
votes
1answer
850 views

Undocumented use of Integrate: Integrating over regions

I have come across a few questions asking about integrating over regions. And while the answers are impressive there should be a better more consistent way. So my question is, are there ways, ...
5
votes
1answer
124 views

Undocumented WolframLibraryData::evaluateExpression

It seem there's this promising function in the callback object provided to MathLink C functions: ...
25
votes
1answer
621 views

Undocumented form for Extract

Prompted by a comments conversation here, here's an interesting (and often performance enhancing) use of Extract: ...
5
votes
0answers
105 views

SparseArray internal structure [duplicate]

According to the documentation: SparseArray is treated as a raw object by functions like AtomQ and for purposes of pattern ...
7
votes
1answer
335 views

How to use Undocumented Functions Prism, Tetrahedron and Hexahedron

Taking a look at this question and this one, I checked to see if Mathematica really does not have a Prism primitive. To my surprise the function ...
18
votes
1answer
526 views

What does ImageSize -> 1 -> 1 mean?

On the page http://www.wolfram.com/language/gallery/blur-faces-in-an-image/ the example code has ImageSize -> 1 -> 1. I am unfamiliar with this chaining of ...
22
votes
1answer
504 views

How to work with Experimental`NumericalFunction?

This question is intimately connected with previous one: "How to create internally optimized expression for computing with high WorkingPrecision?" Oleksandr R. correctly states in the comment: A ...
15
votes
0answers
201 views

Graphics`Mesh`FindIntersections[ ] fails to detect intersections

Graphics`Mesh`FindIntersections[ ] is an undocumented function for, well, detecting intersections very efficiently. Take a look: ...
12
votes
2answers
354 views

Behavior of Reduce with variables as domain

When using Reduce, I accidentally put a set of variables as the domain. To my surprise, it not only seems that Reduce expects ...
15
votes
1answer
229 views

The second argument of Signature

I've noticed that Signature can have an undocumented second argument. What does it do? Signature[{1,2,3,4}, ?]
31
votes
4answers
640 views

Any ideas on how to use the Region` context?

If you type ?Region`* you'll get: which seems a bunch of interesting and not documented symbols. Any idea (or experience) on how to use them? Edit By ...
6
votes
0answers
193 views

Documentation for user-defined functions; undocumented documentation feature?

I stumbled on some strange behaviour when trying out the new function template and documentation features, now purportedly working in v 9.0.1. I defined a function ...
4
votes
0answers
62 views

“ClosingActions” option for FrontEnd`AttachCell

I'm looking to find the possible values for the ClosingActions options FrontEndAttachCell. I have found ...
8
votes
1answer
129 views

Strange behaviour of Internal`InheritedBlock

I was going to post an answer for fast way to replace all zeros in the matrix. I was even quite happy because timings were the same order of magnitude as others. The idea was to overwrite ...
5
votes
1answer
88 views

Syntax for FrontEnd`SelectionSetStyle

I know FrontEnd`SelectionSetStyle is undocumented, but its name suggests it does what I need. What is its syntax? I have already tried several variations of the ...
21
votes
2answers
554 views

How to write beveled fractions?

How to write beveled fractions like ${}^a/_b$? In contrast to $\frac{a}{b}$ and $a/b$ (see this question).