# All Questions

913 views

### How to map an image to get an illusion of 3D

I would like to distort or map a given jpg so it looks 3D when viewed from certain angle, as in the following youtube video: http://www.youtube.com/watch?v=IfCCUd8mFtg. The most interesting part of ...
216 views

### Creating documentation for sub-packages in Workbench

I'd like to create proper documentation for a package of mine, and Workbench in principle provides the tools to do this. However, I've split my package into multiple sub-packages (because I found it ...
361 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, ...
317 views

### Using Boost with CreateLibrary

I was looking at the answer of Leonid of Faster alternatives for DayOfWeek and wanted to see how hard it would be to do something similar in C++ using an external library like Boost. I tried to ...
300 views

### Is it possible to cause a notebook to be hidden when pressing the close button?

Is it possible to cause a notebook to be hidden (Visible -> False) instead of closing it when pressing the close button in the title bar? The ...
160 views

### GraphicsMeshFindIntersections[ ] fails to detect intersections

GraphicsMeshFindIntersections[ ] is an undocumented function for, well, detecting intersections very efficiently. Take a look: ...
291 views

### Is there a guideline about when to end expressions with semicolons?

Whether for nested Ifs or within scoping constructs like Module and Block, I never know ...
844 views

### What compilers are “suitable” for CompilationTarget->“C”?

The documentation for CompilationTarget says, "if you do not have a suitable C compiler then you will not be able to set CompilationTarget to C". Well at this time, I don't have a compiler installed ...
1k views

### How to determine how much of a table is generated?

If I'm generating a table from a slow function, like this: foo = Table[SuperSlowExpression, {1000}] is there a way to determine after submission (so it is too ...
204 views

### How do I override options with my own defaults?

I'm calling a function f from within a function g and would like to pass any valid options for ...
207 views

### Graph smoothing keeping vertices fixed?

Context Given a Graph like this one: ...
219 views

### Temporal database reconstruction in mathematica

<EDIT> after some internet research I found the database domain that deals with this kind of thing: Temporal Databases. I think my question therefore becomes how to reconstruct a temporal ...
268 views

### Making a Mathematica package manager?

I'd like to get a serious discussion started about a package manager. This has come up elsewhere, and many people have implemented their own solutions. It would be nice to have a standardized way to ...
408 views

### Dynamic visualization of Graph[] on a webpage

How can we embed a dynamic version of a Graph object on a web page, similar to the one showcased on the networkx home page? This sort of dynamic visualization can ...
579 views

### Finding the perimeter, area and number of sides of a Voronoi cell

Does anyone have any suggestions how to determine the perimeter, area and number of sides of each Voronoi cell in Voronoi diagram?
4k views

### How to change default notebook background color?

How does one change the default notebook background color?
364 views

### How to export .mtl files for 3D textured objects

I would really like to deploy my textured 3D graphics in the web with sketchfab in my blog. Unfortunately, Mathematica only exports the shape of the 3d graphics, i.e. the .obj file, but omits the ...
300 views

### How can I extract the outline of bubbles in my image?

I have an image: I tried to extract the outline of the bubbles, but I met with some problems. Firstly I tried the method used in Mathematica documentation for ...
458 views

### Exporting data extensions in fits file

Context In Astronomy the de facto standard for images and data is FITS. I would like to export heterogenous data sets into a single fits file. Attempt I am ...
737 views

### Roads network visualization by thickness and color intensity by population from GIS files

We can have road networks of the countries in GIS shape file.For exmple from here. Normally traffic flows are proportionate to populations of the cities. I wonder how we can have the same in ...
290 views

### Searching linked lists that contain lists?

Following the advice I've read here and other sites, I've been trying to use the Mathematica equivalent of a linked lists... ...
633 views

### Relational joining of tables

A common thing to want to do with data is to combine it (at least I thought this was a common thing). In SQL there is the idea of table joins "select id,v1,v2 from A,B where A.id=B.id" kind of thing. ...
208 views

### Calculating probabilities symbolically

Is there a way to solve for statistical quantities analytically/symbolically in Mathematica? example 1: Lets say that I want to do a calculation that requires Bayes theorem. I know p(a), p(b) and ...
732 views

### Can you apply the Cellular Automata function to a grid containing numbers?

Im attempting to simulate a simple evacuation model using cellular automata theory.My study aims to determine whether Cellular Automata can effectively represent how people would behave in a fire ...
284 views

### Manually specifying distance metric to Nearest slows down calculation

Why does manually specifying the distance metric to Nearest slow down the calculation so much? This is relevant to my previous question. I've been using ...
486 views

### 1D quasicrystal: points on a line nearest to points on a lattice

I have a simple lattice / line manipulation: ...
548 views

### Is there a built in function to obtain the back diagonal of a matrix?

Given the following matrix: m = Array[Subscript[a, #, #2] &, {4, 4}] how can I find the skew diagonal or anti-diagonal or back diagonal of the matrix ...
789 views

### OpenSCAD like functionality with Mathematica?

I keep seeing reference to use of Mathematica as a CAD tool (for instance: http://www.makerbot.com/support/guides/design/). I'd like to use it as such if feasible, but I'm having trouble locating ...
647 views

### How to map rotate, pan, zoom to manipulate controls

I am wondering if there is a way to restrict the motion of the rotate mouse cursor in when moving around a 3d plot. For example, I want the y direction of the cursor to correspond to pulling the z ...
277 views

### Import iTunes xml data and convert it into a dataset or table

I have an xml file with song data from iTunes (https://dl.dropboxusercontent.com/u/1012958/iTunes%20Library.xml) and I'd like to import it to Mathematica to do some statistics. I get an XMLObject like ...
7k views

### Quick Hessian matrix and gradient calculation?

I am absolutely new to Mathematica and I actually want to try implementing a little optimization method . Long story short assuming I have a predefined two-variable function f(x,y) I want to ...
314 views

### Exporting BarChart3D as PDF produces artefacts

So I think the following image already shows the problem, similar to Avoiding white lines inside filled area in RegionPlot exported as PDF or PS the pdf export of the chart creates thin lines in the ...
970 views

### Hodrick–Prescott filter (one-sided version)

I am interested in implementing Hodrick–Prescott filter (HP filter) on my time series data in Mathematica. I know that there is already a version of two-sided original filter for Mathematica (see ...
1k views

### Extracting polygons from 3D contour plot surface

Edit: This question turned out to be two parts so I am going to make this question about only the first part a kguler provided an excellent answer. Here is a better representation. My actual data ...
243 views

### How can I create a colour image using raw black and white data? (FITS data cube)

I have a data cube containing pictures of a galaxy across a thousand wavelengths. I want to take the data for the image slides in the red and blue parts of the spectrum, and have them represented in ...
878 views

### DeleteDuplicates not deleting duplicates

It is not surprising that DeleteDuplicates[{5,5.}] returns {5,5.} because DeleteDuplicates ...
369 views

### Are greek symbols causing different evaluation?

I've updated today to Mathematica 9.0.1.0 from version 8 and found something that absolutely confuses me. Let us define a piecewise function: ...
608 views

### Compiling ColorFunction for faster complex phase-amplitude plots

I have gotten into the habit of plotting complex-valued functions on a plane using a color-function along the lines of ...
376 views

### Efficiently appending points to a NearestFunction

I have a program which works with a list of points (in 3D, but it could be in 1D as well, it won't make a difference). Within a loop, it keeps adding new points to the list. To calculate the ...
493 views

### Real Numbers in the Wolfram Language

Epilog: Much of the discussion in the answers below revolves around the distinction between Real as a data type and real numbers as a domain or class of numbers (irrespective of the form in which ...
733 views

### Is there a Mathematica barcode reader?

Is there a Mathematica barcode image reader (much like TextRecognize) that allows the user to enter an image of a barcode and then read it to get an output string?
233 views

### BitShiftRight produces incorrect results in Version 10

fixed in 10.0.2 With Mathematica 10 for Mac, BitShiftRight works properly on lists of up to 100000 numbers, but appears to give incorrect results when threaded ...
1k views

### Elegant and fast way to join all string sequences

I want to do what title says: {"a","b",1,2,3,4,"a",2,2,2,"edg","?"} => {"ab",1,2,3,4,"a",2,2,2,"edg?"} in the most elegant way. For example one replacement rule for ...
1k views

### In a ListPlot of LinearModelFit, Fill to the regression line

In the help for LinearModelFit, the regression line can be added to the scatter plot like this: Show[ListPlot[data], Plot[lm[x], {x, 0, 5}]] Is it possible to ...
1k views

### Using ImageCapture to access a USB webcam in linux

Is it possible to access a USB webcam through Mathmatica on Linux? When I run ImageCapture[] I get the following output ...
494 views

### Mathematica 10.1.0.0 (OS X) high CPU usage even for empty notebook

Since update to 10.1.0.0 Mathematica has a high CPU usage even when no evaluation is running (even for empty notebook opened). I am running OS X Yosemite 10.10.3 on the following configuration: ...
459 views

### Color scheme used by Colorize?

The Colorize function is often used to display the results produced by MorphologicalComponents: ...
309 views

### Why some built-in functions are slow

I just wonder why some built-in functions are slower compared to some other ways using more than one built-in functions for doing same job. consider this example: ...