4
votes
2answers
162 views

Confusing ReplaceRepeated & Hold

I've been bootstrapping myself to the very alien world of Mathematica and there came my first WTF moment: ...
30
votes
5answers
7k views

Custom arrow shaft

Inspired by Sjoerd C. de Vries' nice answer to this question, and the desire to pimp a Graph I did with Mathematica recently I would like to know if there are ways to customize the arrow's shaft ...
2
votes
1answer
208 views

Numerical comparisons of matrices

I have a matrix which should be equal to a null matrix. However due to the numerical precision, a brutal equality test with a matrix initialized with zeros does not work. How should I perform the ...
0
votes
1answer
870 views

Help to solve Simultaneous Equations

I think this should be easy to numerically solve in Mathematica, but for some reason I'm not finding the correct way to do it. I basically want to solve these simyltaneous equiations: ...
1
vote
2answers
103 views

NSum generates a warning message when getting the sum of a list

I know what I'm doing can be done with Total: a = Range@3; Total@a And if I simply choose ...
3
votes
1answer
827 views

stationary distribution of a transition matrix

How can I solve the stationary distribution of a finite Markov Chain? In other words, how can I estimate the eigenvectors of a transition matrix?
1
vote
1answer
478 views

How do I make my discrete plot thicker?

I am making a discrete plot and a regular function plot together. But my curve is so thick that for color-blind people, it's pretty much impossible to see the black dots of my discrete plot: ...
0
votes
0answers
109 views

Good Introduction / Tutorial to Mathematica **Books** [duplicate]

Possible Duplicate: Where can I find examples of good Mathematica programming practice? I'm a high school senior and am using Mathematica for a research project. However, I find it a bit ...
3
votes
1answer
114 views

How to give ClusteringComponents initial values?

I came across a variant of k-means that adds a algorithm to select good starting values called k-means++. ...
17
votes
1answer
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 ...
14
votes
1answer
571 views

Simulating Stochastic Processes the MMA way

This question is really a specific problem and a methodological one concerning MMA best practices. I want to simulate a system of stochastic processes. If this were a geometric Brownian motion or ...
2
votes
1answer
233 views

Getting the 557th element of a table

Make a table with elements $\sin(\sqrt{8 n}/4) + r\, $for $n$ from $1$ to $1000$, where $r$ is a random real number between $-0.1$ and $0.1$ that is different for each value of $n$. Also make a ...
9
votes
2answers
1k views

Using J/Link to decode Google Maps Polyline strings

I would like to use this java code inside Mathematica using J/Link. It converts Google Maps API Encoded Polylines to a list of points. I tried the Mathematica tutorial but got lost. There is the Java ...
12
votes
2answers
522 views

Proper Filling of Self-Intersecting Polygon

I have a spiral pattern that I would like to fill, which self-intersects. My desired behavior is to have filling between neighboring lines only, and to represent this figure as a single polygon. The ...
2
votes
1answer
497 views

How draw dynamic empty rectangle over a bitmap?

I am trying to make a cookie cutter that will extract a small square from a much larger bitmap with a click of the mouse. The LocatorPane appears to be a useful way ...
1
vote
2answers
257 views

Saving graphics object in order to manipulate it later?

I've generated a bunch of graphics using ContourPlot wich, given the nature of my problem, take a long time to create, and I was wondering if there is a way to save ...
9
votes
1answer
361 views

BUGS-type calculations in Mathematica

Recently I have been teaching myself how to Bayesian calculations with the BUGS language (JAGS, in particular). However, I find myself wondering how one might use Mathematica to do similar ...
4
votes
2answers
646 views

Split string into sub-strings of length n [duplicate]

Possible Duplicate: Partition string into chunks How can I split a string into sub strings of length n? For example I have a string "ABCDEabcde1234" ...
3
votes
3answers
701 views

Superscript prime symbol

x\[Prime] looks like $x_'$, ugly right? Is there a way to make a symbol with prime to look like $x'$? That's what I'm trying right now: ...
6
votes
1answer
1k views

Mathematica won't give eigenvectors but Wolfram Alpha will? What am I doing wrong?

If I ask Mathematica to find the eigenvectors and eigenvalues of the matrix: ...
9
votes
1answer
228 views

Ranking Function Allowing for Ties

I have a list that I need to be able to assign ranks to individual elements in, giving it a number related to its position if the list were to be sorted, allowing for ties. For example, ...
31
votes
6answers
2k views

ColorData[“VisibleSpectrum”] is wrong?

I am trying to visualize the visible spectrum using the built-in ColorData["VisibleSpectrum"] function which "colors based on light wavelength in nanometers". But I ...
5
votes
3answers
154 views

Metaquestion: how to find out why (e.g.) MatchQ[42, _?Function[x, True]] is False?

Suppose you run into a bewildering Mathematica result (which happens to me several times per Mathematica session, even after a 20-year acquaintance), such as, for example: ...
4
votes
0answers
165 views

Getting EPS imports to respect the original fill rule

One major problem in my attempt to answer to the CountryData flags question is that the way Mathematica handles filled curves differs from the way SVG and EPS style editors do. The latter two have the ...
6
votes
2answers
559 views

Web scraping and multi-threading in Mathematica

I'm working in some web scraping using Mathematica, and today, to speed-up the process, I used bash commands (xargs with parallel options with curl and wget) using ...
4
votes
1answer
519 views

RevolutionPlot3D of 4 piecewise functions around X-axis crashing mathematica

I'm trying to rotate 4 piecewise functions around the X-axis using RevolutionPlot3D. The 4 functions I have are: ...
3
votes
1answer
446 views

Second Order Non Linear Differential Equation

I'm trying to solve the following differential equation numerically: ...
2
votes
2answers
123 views

Recursion doesn't happen any more or doesn't happen correctly if I store the recursive relationship in a variable first

I know the following code will form a recursion: Clear["Global`*"] u[i_, n_] := u[i - 1, n] + u[i, n - 1] u[0, n_] := n u[i_, 0] := i u[2, 2] (* => 8 *) But ...
5
votes
0answers
93 views

Download binary file bypassing Import/Export? [duplicate]

Possible Duplicate: Downloading files without using Import While attempting to answer my own question I realized that I don't know a way to simply download a binary file to a specified ...
13
votes
1answer
406 views

Transform an expression into a graph that can be plotted with TreeGraph (not TreeForm)

I would like to plot an expression (like TreeForm does), but using the new TreeGraph functionality. ...
3
votes
1answer
456 views

How can I forecast time series data with cellular automata?

I have a time series data, for example data = FinancialData["JK:ADRO", "July 16 2012"] Can I use CellularAutomaton to ...
0
votes
1answer
267 views

FindRoot on a 2D list of Equations

I have a $n \times k$ Matrix of data that I want to feed into an equation and solve for an unknown variable. I suppose I can always just convert the Matrix into a long Array but I'd like to learn how ...
7
votes
3answers
447 views

How to Gather a list with some elements considered unique

I have a list of the form: list={{0,...},{1,...},{1,...},{0,...},{3,...},{3,...},{0,...},{0,...},{5,...},{5,...},{5,...},{0,...},{5,...},{0,...},...} So when we ...
5
votes
1answer
653 views

Splitting a list using SplitBy, by comparing adjacent elements [duplicate]

Suppose that I have the following list called mylist: mylist = {80.2, 80.3, 80.4, 327.6, 327.7, 327.8}; I would like to split ...
6
votes
2answers
214 views

How to make each node of a graph a button?

A newbie question this one - MMA help seems to suggest it would be possible to place a button on ( or have a button be ) each node of graph, labelled with the name of said node. I have no idea where ...
6
votes
1answer
480 views

Indenting bulleted lists in Notebooks

I currently use Word for notes, making nested bulleted lists as I go. I've just started using Mathematica and would like to do the same in its Notebooks, but it doesn't look like it has that ...
22
votes
4answers
1k views

Do people actually use UpValues?

I know what they are and how to define them. They have to serve some purpose - else why include them? But I never used them and all examples on this site and the docs never show a practical use of ...
1
vote
1answer
130 views

Why doesn't Normal[] work?

I have a polygon on which I'm applying a GeometricTransform and I want to get the coordinates of the transformed polygon. ...
3
votes
0answers
62 views

Automatically including custom stylesheet with notebook [duplicate]

Possible Duplicate: How can I easily eliminate the dependency of a stylesheet on a non-built-in stylesheet? For some work I am doing, I take my notes in a notebook with a custom stylesheet. ...
5
votes
0answers
236 views

Second-Order Feedback Pathways

I'm relatively new to Mathematica and I've tried searching and reading through the Mathematica documentation but I'm not able to find a good place to start. I want to model a simple, second-order ...
0
votes
1answer
522 views

How to export a 16 or 32 bit TIFF file

I have a function that creates a monochrome grayscale image that must be export as a 16-bit and 32-bit TIFF file. The Mathematica documentation mentions that these bit depths are supported during ...
1
vote
1answer
2k views

Converting polar coordinate expression to cartesian coordinates

An intermediate step in my analysis requires me to work in polar coordinates, but I would like to convert the results back into cartesian coordinates. The conversion is very simple but tedious for ...
2
votes
4answers
321 views

plot data differences

I have the following data: ...
0
votes
2answers
130 views

How to avoid restart during development? [duplicate]

Possible Duplicate: How do I clear all user defined symbols? During package development things get messed up quite often. (especially when playing with notations) Is there a simple way to ...
0
votes
1answer
67 views

How can I restrict a notebook to evaluate only if I am user 'root'?

I am playing with openCL on Linux with an AMD gpu, and due to a glitch in the driver, I need to be 'root' to get stuff to work. Installation question here.
3
votes
0answers
161 views

Notation Package Quirk for single Symbols

I encounter the following quirk in the Notation package: consider the following ==> and <== declarations ...
33
votes
5answers
2k views

Can the banner in the Home Edition be removed?

The Mathematica Home Edition shows a banner at the top of every notebook: Is there a way to (permanently) get rid of it, without violating the EULA? Edit Yesterday, I sent this message to WRI ...
2
votes
1answer
400 views

How specify PlotRange and display bitmap over plot in DateListPlot?

The problem came up in a plot of RGB data obtained by imaging the variable star d-Cephei with a DSLR camera on several successive nights. I tried to plot the R, G, B intensity points for each day in a ...
2
votes
1answer
435 views

Defining regions for `Exclusions`

I have the following function I want to plot in 3D (For simplicities sake we can say $a=5,b=-1,c=3$.) ...
10
votes
2answers
403 views

How to deduce a generator formula for a polynomial sequence?

Consider a polynomial sequence $\{p_n\}$ generated by some (simple) rule: $$ \begin{array}{l} p_1(x)=x \\ p_2(x)=2 x-x^2 \\ p_3(x)= x^3-3 x^2+3 x \\ p_4(x)=-x^4+4 x^3-6 x^2+4 x \\ p_5(x)= x^5-5 ...

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