11
votes
2answers
196 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 ...
11
votes
2answers
206 views

Graph smoothing keeping vertices fixed?

Context Given a Graph like this one: ...
11
votes
1answer
267 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 ...
11
votes
1answer
380 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 ...
11
votes
2answers
566 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?
11
votes
4answers
4k views

How to change default notebook background color?

How does one change the default notebook background color?
10
votes
2answers
207 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 ...
10
votes
0answers
352 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 ...
10
votes
1answer
295 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 ...
10
votes
4answers
448 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 ...
10
votes
2answers
691 views

How to position text labels automatically to not overlap other graphics elements?

I was plotting reciprocal frame projection using Locators for a point to be expressed in terms of both the original basis (also specified with ...
10
votes
1answer
713 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 ...
10
votes
4answers
289 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... ...
10
votes
5answers
613 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. ...
9
votes
2answers
701 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 ...
9
votes
4answers
3k views

How to plot periodic function's graphic?

How to plot periodic function's graphic? For example, f(t) = t when -5<t<5 && f(t+10) = f(t) ...
9
votes
2answers
280 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 ...
8
votes
1answer
175 views

Expanding derivatives of hypergeometric functions

Sometimes Mathematica expresses results of integration or summation in terms of symbolic derivatives of Hypergeometric2F1 function, and cannot further simplify ...
8
votes
3answers
483 views

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

I have a simple lattice / line manipulation: ...
8
votes
5answers
531 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 ...
8
votes
2answers
758 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 ...
8
votes
1answer
638 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 ...
7
votes
1answer
255 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 ...
6
votes
2answers
307 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 ...
5
votes
1answer
921 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 ...
5
votes
2answers
973 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 ...
3
votes
1answer
240 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 ...
28
votes
2answers
865 views

DeleteDuplicates not deleting duplicates

It is not surprising that DeleteDuplicates[{5,5.}] returns {5,5.} because DeleteDuplicates ...
26
votes
0answers
341 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: ...
22
votes
3answers
373 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 ...
21
votes
2answers
710 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?
21
votes
10answers
2k views

How to convert a hex color string to RGBColor?

For example: "#FF8000". How could I convert it to RGBColor or Hue?
20
votes
3answers
472 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 ...
20
votes
2answers
232 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 ...
20
votes
7answers
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 ...
20
votes
3answers
2k views

Programming a numerical method in the functional style

I am new to Mathematica and I would like to learn a bit more about functional programming. At the moment I have assignments like programming different numerical methods (for integration: ...
20
votes
5answers
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 ...
20
votes
1answer
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 ...
18
votes
1answer
448 views

Color scheme used by Colorize?

The Colorize function is often used to display the results produced by MorphologicalComponents: ...
17
votes
1answer
302 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: ...
17
votes
3answers
642 views

Can CDF file embedded in a web page receive external parameters?

I know that I can embed a CDF file inside a web page by using: The embed tag. An object tag with an embed tag inside (better than 1). Using the JavaScript provided by Wolfram (better than 2). My ...
16
votes
2answers
399 views

A better “VisibleSpectrum” function?

Since ColorData["VisibleSpectrum"] is wrong I would like to have a more accurate function to use. Can this information be extracted from Mathematica itself?
16
votes
3answers
1k views

Drawing a square root spiral

Here is a start, i'm looking for a nice way. ...
16
votes
0answers
158 views

A bug in the overloading of MemberQ and FreeQ for Association?

Bug introduced in 10.0.0 and fixed in 10.1.0. While answering Pattern match for nested Association I came across behavior of MemberQ and ...
16
votes
1answer
250 views

Bug in RepeatedNull?

RepeatedNull appears to be buggy (versions 8.0, and 9.0). Define f as follows: ...
16
votes
1answer
198 views

Standard message definition construct

Why are the messages almost always defined like this (at least in packages): If[Not@ValueQ[function::usage], function::usage = "Usage message"] and not just like ...
16
votes
3answers
490 views

How to get complete Documentation Center graph of guide pages?

On the very last image below you can see a typical path of walking through Documentation Center guide pages. What is the best way to get the graph data and visualize the whole structure of these ...
15
votes
1answer
141 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 ...
15
votes
1answer
435 views

List of atomic expressions

I was surprised to see Graph objects are atomic. Is there a way (through documentation or programmatically) to find all atomic heads? The ones I know of are: ...
15
votes
1answer
316 views

Unpacked eigenvectors of complex matrices

Edit: This bug is fixed in Mathematica 10.0.0 I want to calculate eigenvectors of a Hermitian matrix. For example ...

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