# All Questions

3k views

### How to embed fonts when exporting Mathematica graphics as PDF

Upon exporting a Mathematica graphics expression as a PDF, Mathematica does not seem to embed any nonstandard fonts used. When you open the resulting PDF document with a PDF viewer, all the text items ...
432 views

### General techniques for creating complex animations

I love good animations of abstract concepts, and when I try to create them myself, I prefer doing so in code to make sure they are exact (and because some things are just way too fiddly to do by hand)....
848 views

### What is the natural way of using Dataset to get a FittedModel?

The new Dataset in Mathematica 10 is a great addition to the language, potentially reducing the convenience gap with R. Given this, I would like to understand what the equivalent simple or natural ...
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### Using the Krylov method for Solve: Speeding up a SparseArray calculation

I'm trying to implement this Total Variation Regularized Numerical Differentiation (TVDiff) code in MMA (which I found through this SO answer): essentially I want to differentiate noisy data. The full ...
1k views

### Schedule programing problem with integer linear programming

I know how to model this question on paper, but I don't know how doing it in Mathematica. Imagine , there is a university student who want to choose courses for this semester and he got the ...
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### Does parallel programming use up large quantities of memory in Mathematica?

When I start Mathematica with a fresh kernel and load a program I am developing to analyze biology data, the amount of used system memory is 1.9 GB (free memory is 14.5 GB). These memory values are ...
507 views

### If I have a very large Popup Menu list how can I make that searchable?

Imagine that you have a PopupMenu's list that requires a lot of scrolling through the selections. Is there a way to create a control that will only display a ...
824 views

### Can someone explain this snippet: (#[#] &)[#[#][#] &]

A friend showed me this snippet of code today: (#[#] &)[#[#][#] &] I can sort of see that we're constructing an anonymous function that takes a function ...
1k views

### How to extract the edge from a set of points

I have an accumulation of points representing a body as you can see in the image below. From this data I want to generate a list of points or a curve, which is the envelope. The first idea was a ...
649 views

### Fast DensityPlot

Is it possible to increase the perforamce the DensityPlot? For example, let's try to plot this "flower" ...
207 views

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### How can I detect if an image is in or out of focus?

I need to filter out bad (blurry or ) images from a set, with some sort of blur detector.
3k views

### Axis/Angle from rotation matrix

With r=RotationMatrix[a,{x,y,z}] I can compute a 3D rotation matrix from axis/angle representation. Given a 3D rotation matrix r...
1k views

### How to train a convolutional neural net on images?

The functions Predict[] and Classify[] both have the option Method -> "NeuralNetwork", ...
141 views

### How do I expand StirlingS2[n, 10] in terms of elementary functions?

I know that it is possible to expand StirlingS2[n, 10] in terms of elementary functions of n. I tried ...
2k views

### Longest path in 0/1 matrix

I have a matrix of 0's and 1's forming a number of disjoint paths:   I would like to find the lengths of the paths, and from that "spectrum," the longest length (in the above example: 27, ...
379 views

### How can I evaluate untrusted Mathematica code in a sandbox?

Is there any way to build a sandbox to evaluate untrusted Mathematica expressions in order to prevent them from having (malicious or accidental) harmful side effects? Context: I'm developing a system ...
2k views

### What is a type in Wolfram Mathematica programming language?

"Everything is an expression" is a popular citation from many Mathematica guidebooks. So, what is type in Mathematica? How does it relate to common types from Haskell, for example? I did some ...
1k views

### Graphical representation of a moving sound source

Some explanation since I have got a specific and another more open-ended question: I used two microphones in a 90° arrangement (see picture below) to capture sound from a source moving around the room ...
7k views

### What are the advantages of using .nb rather than .m files?

I can edit a notebook within the mathematica front end and then Save As a .m file, which produces output like this: ...
1k views

### How to plot a figure like this

I saw a beautiful figure illustrating the optical lattice clock, and would like to make a similar one. This is the figure (taken from here) Is it possible to make a similar one using Mathematica? ...
584 views

### How to write Morse code into Plot Dashing?

How can we define a dashing pattern in a plot such that it reads arbitrary text in Morse code? For instance Graphics[{DotDashed, Line[{{0, 0}, {5, 0}}]}] ...
598 views

### Detecting components in timeseries

I'm looking at this sequence of values: I'd like to detect the points where the center of the time-series shifts (around x=1000 and x=2000). Many of the transforms and smoothing methods I have ...
312 views

### What does “EquationalLogicFindCounterexample[]” do?

I found the undocumented EquationalLogicFindCounterexample[] by browsing the lists of available symbols, but I have no clue about its purpose. The name is ...
2k views

### Mathematica color schemes for the colorblind

Does Mathematica have a graphics option that makes plots intelligible for people with colorblindness?
2k views

### Creating diagrams for category theory

Lately I've been doing algebra and I have found myself drawing a bunch of diagrams when I attempt to solve a problem. Most of the diagrams are very simple so I thought, I bet I can do this in ...
297 views

### How can I make Plot show the plot while it's computing it?

Normally, Plot acts like a black box and only gives you the requested plot once it has finished computing it. However it can be useful, other than interesting, to ...
9k views

### How can I save both the plot and the legend together?

In this example, how can I put the legend inside the graph? Currently, when I save the graph, only the graph is saved, not the legend. ...
2k views

### 2D Heat equation: inconsistent boundary and initial conditions

I'm attempting to use NDSolve on a 2D boundary value problem with initial conditions. Upon running my code, I get the following message: "NDSolve::ibcinc: Warning: Boundary and initial conditions are ...
866 views

### Exclude data from a list

Let's create some random sample data data = Table[{RandomReal[{-10, 10}], RandomReal[{-10, 10}]}, {i, 1, 300}]; Then we plot them using ...
734 views

### How do I remove Wolfram Branding in a CDF?

I have a Mathematica Enterprise License, which lets me export Pro-feature CDFs. One of the benefits is supposed to be removal of branding and full customization of UI. Does anyone know how to get that ...
3k views

### Computation of Hankel Transform using FFT (Fourier)

To address circularly symmetric cases of 2-D Fourier Transformations, the so-called Hankel Transform can be applied (for a detailed derivation of the relation between the 2-D Fourier transform and the ...
661 views

### How to make a function with its own options as well as passing options to other functions [duplicate]

I have a function with many of its own options, but I would also like to pass options to subfunctions using the FilterRules function. Here's a simple example: <...
1k views

### How to implement a regular grammar?

What is the most simple, elegant way of implementing a rewrite-system defined as:  \begin{aligned} \Sigma &= \{a_1, a_2, a_3, ...\} \\ N &= \{A_1, A_2, A_3, ...\} \\ \{\alpha_1 , \...
932 views

### Is there a Mathematica API for the functions.wolfram site?

Is there a Mathematica API for the functions.wolfram site? If there's not, has anyone implemented a web scraper for it? For example it would be nice to be able to access http://functions.wolfram.com/...
628 views

### What kinds of uses of SymbolicC (introduced in Mathematica 8) do you foresee? Are there any neat examples already?

Mathematica 8 introduced SymbolicC, a set of Mathematica functions that capture C language constructions in the familiar Mathematica tree-like fashion. Additionally, there are functions to write ...
782 views

### Counting radial ridges on an image

After happily using the v9 image assistant to crop elliptically an image, and then the drawing tools to put a white disk in the middle, I turned this image: into the following one: that can be ...
795 views

### Strategies for solving problems involving searches

As an example of a search-oriented problem, consider finding all constrained $n$-colorings of a graph. An "$n$-coloring" associates one of $n \ge 1$ colors to each vertex in such a way that no edge ...
1k views

### Hightlight all the self-intersections of a Lissajous figure

This graph–also known as a Lissajous figure–contains so many self-intersections.How can I highlight them? ...
3k views

### Vectorizing an image like “Trace Bitmap” in Inkscape

Lately, we had a nice question about artistic image vectorization which got very nice answers. As Szabolcs pointed out himself Since "true" vectorization performed by various specialized software ...
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### How do I extract the middle element(s) of a given list?

How do I extract the middle element(s) of a given list? Here is some code that works, but seems a little too long: ...
898 views

### Computing polynomial eigenvalues in Mathematica

MATLAB offers a function polyeig for computing polynomial eigenvalues, which appear, for instance in quadratic eigenvalue problems (see here for some applications) such as: (M\...
894 views

### How to get a plot generated by R returned in an output cell?

It seems we'll never have built in two axis plots and list plots in Mathematica but you can make them in R. ...
2k views

### Using Inset[..] to overlay a Graphics3D with its raster version

Preamble First let me explain the why. You can skip this and go directly to the question if want to answer it right away. We had more than one discussion about how to produce nice looking 3d plots ...
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### How to measure segment length and branch angle

I am trying to measure segment length and branch angle or bifurcation angle between each pair of segments. My image after thinning looks like this: ...
416 views

### Notebook vs. DocumentNotebook; display a Notebook inline, like a DocumentNotebook

If you evaluate a DocumentNotebook[] expression in the front-end, it nicely displays inline, inside of an output cell in the current notebook: For my purposes, <...
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### How do you find the frequency and amplitude from Fourier?

Edit This is a popular question with several answers. This edit organises the answers and gives links. Fourier just gives y values (ordinates) if you wish to read off frequencies and amplitudes you ...
360 views

### Creating a cloud of blocks that form I ♥ U in different viewpoints

This picture shown bellow has three shapes with different view angle (I ♥ U). How to do this type of model? A few tries: ...