# All Questions

73 views

### Unknown (internal?) function with DSolve

I am solving With Mathematica 10 the following ODE system: DSolve[{B'[x] == -f[x]*Cos[l]*G[x], G'[x] == +f[x]*Sin[l]*B[x]}, {B,G}, x] The solution is almost ...
68 views

### Symbolically Minimizing a Max function

I'm having a tough time with seemingly simple symbolic Minimization/Maximization in Mathematica. I would like to use the Maximize function to work on some unknown random variables and so use min/max ...
78 views

### Region Intersection for MeshRegion objects embedded in 3D

How can I create a logical intersection of MeshRegion objects that are three-dimensional? The RegionIntersection function will ...
30 views

### VertexDelete not working on graph with VertexWeight

Good afternoon, I have observed an "unexpected behaviour" with VertexDelete and a graph with vertex weights. This is a minimal working example: OK ...
69 views

### Obtain $\TeX$ code as in StandardForm

This is a question very close related to Breaking up long equations in TeXForm. Last time, because @Adam doest not present a clear goal for this problem, as stated by Massimo Ortolano there's no ...
72 views

### How to export a Mathematica notebook into Markdown?

Is there a way to do this other than html + pandoc?
92 views

### Detect touching particles in image

I have a picture of glas spheres. I want to calculate different properties of these spheres such as circularity, size and count them. I have managed to fill the white centers of the particles to ...
44 views

### Interval Arithmetic with Symbolic Intervals

I've run into a problem with IntervalUnion and IntervalIntersection when dealing with symbolic intervals. The following code ...
48 views

### Export to MX seems to corrupt the in-memory Dataset

I have a function that does a large number of calculations (by calling out to other smaller functions), and then builds a large Dataset object. Then I do two ...
69 views

### Fitting data to plot using errors as weights

I have some enzyme kinetics data that I want to fit to the Michaelis-Menten curve in order to obtain the kinetic parameters of the enzyme. Is it meaningful, statistically and functionally speaking, ...
55 views

### Undo automatic update

I was working with Predict function (with a neural network and today, and when I executed the same notebook I have been working for some time, Machine Learning package was automatically updated (it ...
87 views

### Discrepancy in the series expansion of $\log(z/(z-1))$ in Mathematica 5

When I calculate the series expansion of $\log\frac{z}{z-1}$ around $0$ in Mathematica 5.2, I obtain: ...
42 views

### Indeterminate expression 0(I*Infinity]) on indefinite integrals on first use only

I do not know if this is new or not, I googled before. Windows 7, 10.1 64 bit: Integrals generate this error message The strange thing also is that the message shows up the first time the command ...
51 views

### Applying functions to irregularly distributed Keys in Association lists

This Q is related to this one, but now refer to the situation as irregularly distributed Keys in lists of Associations: ...
63 views

### How to match the arguments of the function in any order

The issue is the following, with a dumb function with (4) arguments of (4) different heads (for each head is always no grater than one arguments): ...
50 views

### Different FourierParameters in each dimension for discrete Fourier transform

I have a query about the Fourier utility, that does discrete Fourier transforms. I am unable to find any information on whether different FourierParameters can be used in each dimension. This is a ...
86 views

### DiracDelta and version 10.0.0

Note: This issue seems to affect version 10.0.0 only and is fixed in 10.0.1, 10.0.2, and 10.1 When evaluating the following two inputs: ...
60 views

### Is it necessary to close MathLink connection?

I use WSTP (formerly known as MathLink) program LoopTools (here is the link with executables and source: http://www.feynarts.de/looptools/). To create connection within Mathematica, I use command ...
49 views

### How does Mathematica automatically choose which classifier method to use?

I'm interested in what heuristics are used in Classify's choice of method.
68 views

### LinearSolve and Krylov Method options

I need to solve a large, sparse, linear system. At some point Method -> "Multifrontal" fails and a bit later also "Pardiso" ...
47 views

### Using indexed array elements as integration dummy variables with EvaluationMonitor. Bug?

As part of a routine that must cope with integration of varying numbers of dimensions, I would like to use indexed variable names (e.g., x[0], x[1],...) as dummy integration variables. However, it ...
45 views

### Why does the debugger not stop when a message is generated?

I am on version 10.1. I have enabled the debugger and I have checked the box in front of "Break at Messages" in the Debugger Tools Window. However most the time the debugger does not stop when a ...
97 views

### Help with Fourier analysis and filtering of an image

I am starting with the following image: For the curious, it is an STM scanned image of graphite. I am hoping to find some kind of periodic structure in the image related to the honeycomb structure ...
136 views

### Something like MATLAB Cody for Mathematica? (Learning through exercises.)

At some rainy days, when I realise again the TV program is getting worse and worse ... I visit Cody: Cody™ is a MATLAB Central game that challenges and expands your knowledge of MATLAB. As a web ...
46 views

### Powers of dimensionless quantities: is this a bug?

Today I came across the following behavior: Quantity[x, "Minutes"/"Minutes"]^-1 (* Quantity[1/x, (1/#1 &)[("Minutes")/("Minutes")]] *) It seems that ...
141 views

### How can I scrape the social network for a subset of users in Twitter?

Clearly one cannot scrawl the entire network... but I'd like to extract a statistically representative sample from the network. More specifically, I'd like to access the graph induced by scraping the ...
42 views

### Is there a way to create named ranges for spreadsheet exports?

I am trying to figure out whether I can tell Mathematica to name ranges for data that I am exporting? I want to use this data in CPLEX, which unfortunately doesn't allow the use of the R1C1 notation, ...
81 views

### Problem drawing a GeoPath polygon with GeoGraphics

I want to draw some polygons bounded with various geographic coordinates. For example, here is the code to draw a triangle between New York, Cape Town and Beijing. ...
47 views

### Error when combining Except, “*” and an additional character

Anyone knows why StringMatchQ["x", Except[{"1", "2"}]] StringMatchQ["x", Except[{"*"}]] StringMatchQ["x", {"1", "*"}] (* without Except *) all work as ...
121 views

### Minimalistic code challenge on Apollonian gaskets

I've been recently fascinated by the beauty, symmetry and mathematical richness of the Apollonian gaskets. So I felt myself challenged to see if it was possible to generate one in Mathematica with ...
37 views

### short cut entry in KeyEventTranslations.tr works on V 10.0.2 but does not work in V 10.1

I added 2 useful key shortcuts to my V 10.0.2 KeyEventTranslations.tr to allow adding [[ and ...
52 views

### Smart use of ParallelMap over Plus

I'm looking for ways to speed up calculation of a integral with a many-terms integrant. The obvious way is to go in parallel. I was surprised, but for some tests integration by ...
104 views

### Behavior of TimelinePlot with multiple datasets of associations

The following TimelinePlot behaves as I would expect: ...
83 views

### Differential Geometry on a MeshRegion

For many many years (honestly, since 1987) I've had my own MMa computational geometry code for dealing with 3D meshes. I principally (there's a joke there somewhere) use it to calculate coordinate ...
46 views

### Undocumented options for “BalloonEmbedding” in GraphLayout

From an error message, I see some options of the BalloonEmbedding method for GraphLayout: ...
75 views

### Lisp Interpreter

What is the cleanest way to build a lisp interpreter inside Mathematica. I'm not looking for all the functions to be implemented but instead just the basic syntax.
79 views

### Does Mathematica support an unordered set (e.g. hashset) data structure?

Does Mathematica support any data structure representing an unordered set (without multiplicity) of Mathematica expressions? I would like this data structure to support $O(1)$ insertion, deletion, and ...
119 views

### Mixing Wolfram Language & WolframAlpha Queries - How robust is it?

The advent of Mathematica in the cloud and linguistic input potentially transforms expectations of the Wolfram Language's programming model and its inherent robustness. An example of this comes form ...
102 views

### Finding all zeroes - mysterious missing roots

Finding all the roots of a function of one real variable has been discussed extensively in e.g. Find all roots of an interpolating function (solution to a differential equation) (answer no. 2 by Jens ...
81 views

### Packages and Notebooks as a Databin

The new Data Drop product sounds interesting. Can I use Databin to share Packages and Notebooks? If yes. How? Something like: ...
127 views

### Export to JSON format specifically for MongoDB

It is a nice thing that, if you have a data as a list of rules (even nested), Mathematica can export them in JSON format. After generating useful data in Mathematica, Therefore, it seems it ought to ...
78 views

### Finding and plotting roots with parameter

I have the following function: $$u(x,t)=\sum_{k=1}^\infty\frac{v_0 L}{\lambda_k c \sin\left(\lambda_k\right)}\sin\left(\frac{\lambda_kx}{L}\right)\sin\left(\frac{\lambda_kct}{L}\right)$$ and this ...
130 views

### Obtaining NIntegrate error estimate

Is there a way to extract the error that Mathematica estimates when calculating a numerical integral using NIntegrate? Internally Mathematica must keep track of this error, because it is used to ...
59 views

### WorkingPrecision in LogLogPlot creates wrong plots

I seem to have found a bug with LogLogPlot in version 10. If I specify a working precision, the function produces total garbage. Here is a simple example. The first case, without WorkingPrecision ...
55 views

### How can I set up a cell style that is ascending dates?

Outline style notebooks have cell counters that are simply ascending numbers, but what if I want to apply a function to them and have descending dates like this: So that they auto format and the ...
51 views

### How can I make a stylesheet that counts subcells?

The example cells in the documentation each have count of the cells inside their section: ...
65 views

### Is there a convenient way to sum TimeSeries objects in Mathematica?

Imagine I have two TimeSeries objects, ...
71 views

### Strange extrapolation in ListContourPlot?

I have some Table of {x,y,z} values (energy as a function of radial and azimuthal frequencies in a galaxy if you care to know): ...