Questions tagged [undocumented]
Questions on undocumented functionality of Mathematica. Note that such functions might be subject to change without notice in future versions.
320
questions
1
vote
3
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99
views
Why does assuming f[_] > 0 does not work while Element[f[_], Reals] does?
Refine works with symbols in either way:
Refine[Sqrt[x^2], Element[x, Reals]]
(* Abs[x] *)
Refine[Sqrt[x^2], x > 0]
(* x *)
...
- 31
2
votes
0
answers
30
views
What are the (potential) uses of those utility functions in the context GroupTheory`Tools`?
This old answer briefly described the usages of
GroupTheory`Tools`Multisets,
GroupTheory`Tools`MultiSubsets,
...
- 433
5
votes
2
answers
68
views
Where is the new System`ConvertersDump`$extensionMappings?
I used to find the extensions mapping from System`ConvertersDump`$extensionMappings, which gives a mapping like "{"*.3ds" -> "3DS"...}&...
- 273
5
votes
1
answer
132
views
Graphics`Mesh`FindIntersections not working in Mathematica 13.3
I just updated my Mathematica for Windows to 13.3 and when I tried to use the "Graphics MeshFindIntersections" command it doesn't seem to work. Have they replaced it with some other command ...
- 899
3
votes
0
answers
36
views
What's the effect of SyntaxForm option in StandardForm boxes of Superscript?
Consider the following sample:
...
- 63.8k
2
votes
0
answers
41
views
How do I identify which external routine is potentially internally used when executing some built-in function?
Wolfram's website declares that "a large fraction of Mathematica's numerical algorithms are based on original research at Wolfram Research" (cf. So Many Original Wolfram Algorithms). So, ...
- 433
2
votes
0
answers
90
views
How to obtain documentation on functions inside some of the packages that are automatically loaded by Mathematica?
Mathematica comes with lots of useful functions which seems not to be documented. At least I do not know how to find the API documentation to learn more about these functions and how to use them.
<...
- 137k
5
votes
1
answer
83
views
Custom Graphics primitives can't work with parallel Rasterize
I tried to create Graphics primitives using the techniques in this, found problems with parallel rasterization
...
- 5,562
2
votes
0
answers
143
views
What is the usage of other "*Block" and "With*"? [closed]
There exist some "kernel functions" that are related to the built-in scoping constructs: Assumptions`AssumptionsBlock, ...
- 433
5
votes
2
answers
264
views
What do the arguments of a generated BSplineFunction mean?
For example, if we evaluate this:
BSplineFunction@{{0,100},{200,50},{200,0}}
we'll get
...
- 3,690
5
votes
1
answer
119
views
"Information about the undocumented function Internal`DiracGammaMatrix"
Searching for information on undocumented functions here, I found that there are no references about the use of the undocumented function Internal`DiracGammaMatrix.
Does anyone in the community have ...
- 12.4k
11
votes
0
answers
126
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Eliminate variable with partially documented Solve feature Solve[eqns,vars,elims]. Robust?
The Eliminating Variables section on Manipulating Equations and Inequalities documentation quotes an otherwise undocumented feature for Solve
...
- 36.2k
6
votes
1
answer
135
views
Understanding NDSolve::ndmmc
When running NDSolve with Method->{"EquationSimplification" -> "MassMatrix"} I frequently encounter ...
- 475
1
vote
1
answer
170
views
Trapezoidal method for ODE results in cmsing warning
I try to solve an ODE using the trapezoidal method. I do the following (Definition of Trapezoidal is from this answer):
...
- 561
7
votes
1
answer
83
views
How do I include additional kinds of boxes that are Tab-selectable
Observe that "PlaceHolder" and InputFieldBox are known by the FE to respond to pressing the Tab key:
...
- 19.5k
4
votes
0
answers
80
views
Is there more complete documentation of DSolve with all hacks?
I know DSolve. I know this community and I am able to gather some hacks.
There is this:
...
- 3,996
5
votes
3
answers
204
views
$Assumptions = _ ∈ Reals results in incorrect simplification of ConjugateTranspose[..]
The linear combination $Q$ of two Hermitian matrices $A^\dagger = A, B^\dagger = B$ with real coefficients $m,n \in \mathbb{R}$, i.e. $Q = m A + n B$ is itself a Hermitian matrix $Q^\dagger = Q$.
...
- 53
8
votes
1
answer
193
views
Available Methods for DSolve?
I would like to know, apart from Method->Automatic what are available methods for DSolve.
...
- 299
3
votes
1
answer
152
views
Pattern not matching BoundaryMeshRegion
Mathematica 13.1 on Windows 10.
Can someone explain why the following does not match:
MatchQ[BoundaryMeshRegion[Cube[]], BoundaryMeshRegion[__]]
(* False *)
- 47.3k
3
votes
1
answer
66
views
How to set minimal allowed size for a graphical element?
Starting from version 10.3 there is a documented way to specify a maximum allowed size for a graphical element via UpTo:
...
- 61.5k
10
votes
3
answers
208
views
Context menu to graphics component
How do I add individual context menus (shown upon secondary mouse click) to various components of a graphics object without needing to go into edit mode?
Consider the following example:
...
- 19.5k
2
votes
0
answers
59
views
VandermondeSolve changes, InterpolatingFunctionToPiecewise breaks
I just notice ResourceFunction["InterpolatingFunctionToPiecewise"] is broken in v13.1. (Perhaps it's in v13.0, I'm not sure. ) Here's a sample:
...
- 63.8k
11
votes
4
answers
221
views
How to detect errors that happen in the FrontEnd? [duplicate]
Some errors only seem to be produced at the point of typesetting, making it very difficult to detect them early. For example:
...
- 21.9k
4
votes
0
answers
96
views
NMinimize/NMaximize: How to specify additional options to the "PostProcess"->FindMinimum option
I would like to pass FindMinimum Options to the PostProcess Option of NMinimize.
Here is minimal working example of using NMinimize from the documentation at (see tutorial/...
- 3,968
8
votes
4
answers
267
views
How to determine the current width of the output cell area?
When answering this question, I suddenly realized that it is surprisingly difficult to determine the current width of the output cell contents.
I tried to employ the ...
- 61.5k
2
votes
2
answers
321
views
Why does System`Private`ConstructNoEntry[Quantity, 1, "kg"] enter a Recursion?
System`Private`ConstructNoEntry[BesselJ, 0, x]
works fine, and outputs
BesselJ[0, x]
However,
...
- 17k
11
votes
2
answers
467
views
How can I create an atomic head or treat some head as atomic during Map?
For example,
Map[g, {0, {h[1, 2, 3]}}, {-1}]
gives
{g[0], {h[g[1], g[2], g[3]]}}
I want a ...
- 17k
8
votes
1
answer
469
views
Charting`ScaledTicks not working anymore in Mathematica 13
Charting`ScaledTicks was a convenient way to organize Ticks or Frameticks in Mathematica without needing to define a tick-function. Basically most tick-related questions here were answered with this ...
- 194
6
votes
1
answer
120
views
User plug-in methods for SumConvergence
@Валерий Заподовников remarks:
BTW, it is also quite bad that Mathematica does not have Bertrand test.
Is there a way to extend the convergence tests in ...
- 234k
13
votes
2
answers
255
views
Arithmetic operations on NumericArrays
Currently, NumericArrays are directly supported by the most important array-related functions, what makes them a very attractive data structure for implementing ...
- 61.5k
11
votes
1
answer
324
views
What is idiomatic way to extract NumericArray from Image?
It is easy to see that NumericArray is a construct underlying Image:
...
- 61.5k
10
votes
1
answer
116
views
How to list all possible string arguments of a specific function?
For example, to learn the function Alphabet, we can read its document. But it's rather ambiguous, like "Some languages have extra properties". How to find ...
- 266
2
votes
1
answer
63
views
How to use System`Private`AssumptionAccess and Assumptions`*?
I see this function is used by some symbols in Assumptions`*, and it HasDownCode and does not ...
- 3,690
1
vote
1
answer
263
views
Internal`CopyListStructure makes fatal error sometimes
Warning : At least in my PC (windows 10, mathematica V12.2), some of the codes here led to fatal error.
Fatal means mathematica will freeze + 'Abort Evaluation' will not work. I had to quit the kernel ...
- 4,047
6
votes
1
answer
150
views
What is the purpose of StrokeForm?
Symbol System`StrokeForm is present already in Mathematica version 8 (but not in version 5.2).
Currently, it is used in built-in themes, for example:
...
- 61.5k
3
votes
1
answer
213
views
How to explicitly open or close cell group?
There is a "OpenCloseGroup" in FrontEndTokenExecute. It act like toggle. If the selected cell group is open, ...
- 17k
3
votes
0
answers
79
views
How to convert Graph atomic object back into unevaluated expression? [duplicate]
For the purposes of further development of my shortInputForm function, I wish to convert Atomic objects such as Graph into non-...
- 61.5k
4
votes
1
answer
286
views
Resolve absolute path to Documentation Notebook
We can easily create clickable hyperlinks for Documentation pages like the following:
{URL["paclet:ref/Set"], Hyperlink["paclet:ref/Set"]}
But ...
- 61.5k
8
votes
1
answer
140
views
What Does Compile`SetIterate Do?
The list of compilable functions (given by Compile`CompilerFunctions[] // Sort) shows one of the more interesting- and core-sounding functions: ...
- 1,607
5
votes
0
answers
58
views
What are the valid options for the "ParametricCaching" option in ParametricNDSolve?
I am using ParametricNDSolve as part of the calculation of an objective function for an optimization, so I am trying to strike a balance between memory usage and ...
- 15k
3
votes
0
answers
28
views
Modern equivalent of $InternetProxyRules
The undocumented symbol $InternetProxyRules was useful for debugging network connectivity issues. In Mathematica 12.0 it returns a list with keys "UseProxy&...
- 7,958
21
votes
1
answer
962
views
Is Internal`StringToDouble broken in 12.3?
I believe Internal`StringToDouble was the only way to fast convert string into numbers. Now in V12.3 it was removed:
Internal`StringToDouble["1"]
...
- 26.1k
2
votes
1
answer
138
views
How to set MaxStepSize for the case of two variables
The option MaxStepSize permits to manually set the step size of the integration in NDSolve and similar functions.
How do I set ...
- 6,607
0
votes
1
answer
85
views
TemplateEvaluate, TemplateUnevaluated, and TemplateVerbatim [Undocumented] - What do you know?
Let's discuss some undocumented Template-related functionality. Specifically, what do you know about TemplateEvaluate, ...
- 615
5
votes
1
answer
322
views
NDSolveValue and pdepe of MATLAB disagree under spherical coordinates
Assuming there is a spherical activated carbon particle, the concentration outside the grain is 200 (C[t,ri] == 200), that ...
- 53
6
votes
1
answer
101
views
Turning off automatic hyperlinks
Recently (I only noticed in V12.2), website URLs, such as https://www.wolfram.com, became active in text cells in notebooks. The "hot" nature makes the links hard to edit, since any click ...
- 234k
6
votes
0
answers
71
views
How to revert behavior of SeriesData to pre 12.1
In Mathematica 12.0 and earlier,
SeriesData[x, 0, {1/u + Log[x/y]}, 0, 3, 1]
used to preserve its list of expressions in the form it was given.
Now, in ...
- 19.5k
5
votes
1
answer
149
views
Property "Centroid" of result from ConvexHullMesh[] can not be extracted
As the title describes, specifically, simple code below
ConvexHullMesh[RandomReal[1, {10, 2}]]["Centroid"]
returns an error in V. 12.2, but it worked in ...
- 9,573
1
vote
1
answer
193
views
Log scale for ListContourPlot when the axes have different orders of magnitude
I am trying to plot a data set (download here) in Mathematica (it's 3.9 MB and I wasn't sure how to best share it) which I then want to visualize with ...
- 992
8
votes
1
answer
428
views
Please explain this syntax: GaborWavelet[6]["FourierFactor"]
I've been using Mathematica for some years, yet I'm befuddled by this statement:
GaborWavelet[6]["FourierFactor"]
It appears to give the center frequency ...
- 447