12
votes
1answer
206 views

Solve[ ] with Method -> Reduce gives a different result than Reduce[ ]

Why does Solve[Sqrt[x + Sqrt[x]] - Sqrt[x - Sqrt[x]] == m Sqrt[x/(x + Sqrt[x])], x, Reals, Method -> Reduce] give a different result than ...
12
votes
2answers
1k views

Suppressing negative roots in Mathematica

Problem Using Mathematica's Solve operator can sometimes lead to an output involving a positive and negative root (say when solving for a variable such as ...
11
votes
1answer
201 views

How to specify PDE Boundary condition on Bspline?

Context I would like to solve a PDE on a boundary which is parametrized as a BSpline. I am trying to solve the force-free Grad-Shafranov equation on a ...
11
votes
2answers
188 views

Faster trimming of leading/trailing zeroes in rectangular array

Given a (large) rectangular array, e.g. (small for example case): ...
11
votes
1answer
129 views

Adding Trace produces error messages

This is very strange. As I was trying to debug this problem, I noticed when I add Trace then I get lots of internal errors generated. This also happens the first ...
11
votes
0answers
204 views

Bug in plotting function using FindMinimum?

Bug introduced in 10.0 and persisting through 10.2 or later While working on an answer to RegionPlot from NDSolve, I came across this strange behavior of ...
11
votes
3answers
303 views

What is the best way to flatten a linked list with lists as values?

By following the advice on this site I have ended up with a linked list like the following: acc = {{1, 2}, {{2, 3}, {{3, 4}, {{4, 5}, {{5, 6}, {}}}}}}; This was ...
11
votes
2answers
600 views

Annoying FrontEnd bugs in Mathematica 10

Recently I installed Mathematica 10 on Windows 8 x64 machine. Before that I had a prerelease version of Mathematica 10 installed on my laptop. I observed very annoying bugs in the FrontEnd on both ...
11
votes
1answer
128 views

Possible Bug in ProbitModelFit when used in a Dataset

Since upgrading to Mathematica 10 on Mac OSX I have come across a number of instances of this error, which occurs using Probit and Logit model fit. A bit of googling show this is something to do ...
11
votes
1answer
198 views

Why doesn't repeated PatternSequence work with explicit pattern names?

Why would this work: Clear[f] f[a : PatternSequence[b_, c_]] := {a}; f[1, 2] (* {1, 2} *) and this also works: ...
11
votes
1answer
552 views

Are there tools for getting Mathematica 9 Notebooks working in Mathematica 10?

As often happens with Mathematica updates, nearly all of my notebooks no longer work as they did with the previous version. The upgrade from 9 to 10 has changed the appearance or introduced errors ...
11
votes
3answers
206 views

How to collect expressions from cells created by Print?

I have a notebook where evaluation of a certain cell produced hundreds of adjacent output cells using Print. I need to create a list containing all expressions from ...
11
votes
1answer
260 views

How to find longest monotonic sequence?

I have a list, for example list = {2, 1, 3, 5, 4, 6} How to find longest ascending sequence of this list? There are two meanings of this question: Find the ...
11
votes
1answer
409 views

How to convert a notebook cell to a string retaining all formatting, colorization of identifiers etc?

I have an opened Mathematica notebook containing several cells. Suppose, I am interested in one of them -- it may contain a complete or incomplete expression (e.g. with syntax errors, highlighted ...
11
votes
1answer
512 views

RLink and R v3.0.1?

Running InstallR["RHomeLocation" -> "C:\\Program Files\\R\\R-3.0.1"] results in a popup box titled "Version Mismatch" saying Error: R.DLL version does ...
11
votes
1answer
815 views

NDSolve Differential Equation Error

I am trying to solve the following differential equation- ...
11
votes
1answer
321 views

Overloading second argument of CountryData

For convenience I'm trying to add an extra property to CountryData ...
11
votes
8answers
510 views

Any built-in function to generate successive sublists from a list?

Given lst = {a, b, c, d} I'd like to generate {{a}, {a, b}, {a, b, c}, {a, b, c, d}} but using built-in functions only, ...
11
votes
0answers
376 views

Proving (self) similarity with Mathematica - Reccurrence Plots, Similarity Plots etc

I posted this question in math.se but given the sheer tumultuous number of questions that keep appearing on math.se and also given that I am trying to accomplish this in Mathematica, I thought I'd ...
11
votes
3answers
570 views

Toggle visibility of elements in a plot

I have three simple graphs in one Plot. Now I am trying to make a button for each graph so you can hide or show it in the plot. Until now I was just able to make a checkbox with the Manipulate ...
11
votes
3answers
1k views

Derivatives (divergence, gradient, curl) of interpolated 3D data

How can I calculate a vector derivative (i.e. divergence, gradient, curl) of interpolated data? For sample data, you can use: ...
11
votes
3answers
183 views

Emulating Sequence with my own function

I just considered if/how one could implement Sequence in Mathematica if it were not predefined. It turned out that the following simple definition has in all my ...
11
votes
4answers
2k views

How to convert from base 2 to base n?

I'm trying to use baseform to convert numbers in base 10 to base n, how can I make the convertion between, say base 2 to base n? Baseform seems to always think that the base in expr ...
11
votes
2answers
430 views

Animation: presenting events that persist in time

I have a list of events that occurred on specific moments in time. In the example below, the three events occurred at 23:09, 23:13 and 23:17. I was able to build an animation that flows from time ...
11
votes
7answers
335 views

Question about evaluation control

I want to make a function that takes a function as a parameter and prints an integral with the function inside. I've tried this: ...
11
votes
3answers
272 views

Numbers in alternate bases transcend the evaluator?

It looks to me like a number in a base other than base 10 gets evaluated before the evaluator ever gets a chance to be tweaked. For example, FullForm[16^^abcdef] ...
11
votes
2answers
735 views

How to plot a barycentric line

I want to plot a barycentric function on an equilateral triangle (ternary plot). For example f1 = {Abs[Sin[x]], Mod[x, 2], Abs[Cos[x]]}; At the moment I evaluate ...
11
votes
1answer
436 views

Mathematica implementation of Earth Movers Distance?

Has anyone implemented in Mathematica the Earth Mover's Distance (EMD)? A concept dating back to Monge 1871, used to compare histograms and images, e.g., the CIEDE2000 Color Difference algorithm. ...
11
votes
2answers
682 views

How to set row height in Grid?

I always thought that Grid (and the underlying GridBox) and the general handling of tabular objects is a bit weird in ...
11
votes
3answers
2k views

Poor rendering of fractals

Could someone explain why I get those ugly graphics .. ..trying to use fractals in mathematica 8 ? I'd also like to know if it is possible to draw 2D fractals in Mathematica My configuration ...
10
votes
2answers
299 views

Why can I not replace a Dataset using a rule?

Simple replacement of a Dataset object does not seem to follow the expected behavior... Dataset[{}] /. _Dataset->1 Returns the empty Dataset not 1 as I would ...
10
votes
5answers
364 views

Make a series of points curl

Say I have a series of points that make a straight line... (Fig 1) points = {{0, 0, 0}, {1, 0, 0}, {2, 0, 0}, {3, 0, 0}, {4, 0, 0}, {5, 0, 0}} I can rotate these ...
10
votes
5answers
851 views

The mysterious gap inside Grid

There's this gap inside Grid which I cannot seem to remove. Perhaps someone knows how. ...
10
votes
4answers
589 views

Breaking up long equations in TeXForm

If I have a horrifically long expression and output it to TeX using TeXForm, I get a long equation which needs to be split up into multiple lines. But splitting it up manually can be quite cumbersome. ...
10
votes
4answers
319 views

Efficient way of identifying the indices of first occurrences

It seems to me like identifying the first occurrence of unique elements should take about the same amount of time as it takes to delete duplicates. My data sets are much larger than this (...
10
votes
1answer
567 views

How do I place a texture on an irregular 3D model?

I'm trying to reproduce a textured head in Mathematica, and I'm using a kind of 'net' of a head which contains all the features on the face. The texture looks like this: which is supposed to look ...
10
votes
4answers
1k views

Plotting an epicycloid

I am fairly new to Mathematica and I cannot figure out how to plot an epicycloid. I have plotted some neat looking things in my attempts, but can't make one. I am not looking to make an animation, ...
10
votes
2answers
322 views

PlotRangeClipping not working correctly with small ImageSize and PDF-export

Although Mathematica has some nice plotting capabilities, there are some things which are annoying me: I like to export a Graphics oder Plot to PDF for use in $\LaTeX$. I like to a have an ImageSize ...
10
votes
2answers
272 views

Giving JLink Huge Memory by Default

I have noticed that Mathematica makes use of Java by way of JLink, for example, in the extensions such as DatabaseLink and (I think) RLink. It also seems like Java is a first-class citizen for writing ...
10
votes
1answer
136 views

What are the scoping rules for function parameters shadowing System` symbols?

Here are some very contrived code snippets, highly unlikely to appear in real code, but still I am curious why they behave like this: ...
10
votes
1answer
215 views

Is there a method to enumerate the keys/values of System`Utilities`HashTable

Lacking from the simple API of System`Utilities`HashTable is a method to enumerate the keys/values. ...
10
votes
1answer
446 views

FourierSeries for rational function looks wrong

I have the following code: ser[x_] = FourierSeries[(\[Pi]^2 + a)/(3 x^2 + a), x, 10] // N // Chop It gives me some series, which I then try to plot. And ...
10
votes
2answers
306 views

Determining whether two $k$-chromatic graphs are isomorphic (respecting vertex coloration)

Consider the case where I have two $k$-chromatic graphs $G_1$ and $G_2$, i.e. two graphs where individual vertices can be colored with one of a set of $k$ total colors, and I would like to determine ...
10
votes
1answer
420 views

How to make a volume CUDA rendering isometric?

I just realized that the output of CUDAVolumetricRender[] uses (quite marked) perspective, which I do not want (for scientific data representation, it can be very ...
10
votes
1answer
203 views

Why do DateList, DateString, and AstronomicalData ignore $TimeZone?

My reading of the documentation for DateList and DateString lead me to believe that both functions use ...
10
votes
1answer
668 views

Changing default ImageSize in the frontend?

I would like graphs to appear somewhat larger in my notebooks (running v8.0.4 on OSX 10.8.2). Naturally I can specify ImageSize in each individual plot, or drag ...
10
votes
1answer
397 views

Symbolic Integration along contour: branch cut problem?

Context Following this question on path integrals in the complex plane, having defined again a numerical and symbolic integrator along a path as ...
10
votes
1answer
175 views

Algorithm used by IsomorphicGraphQ

I'd like to know which algorithm is used to test if two graphs are isomorphic?
10
votes
3answers
656 views

Mathematica Plot: Inconsistency when plotting large values

I am working with a function in Mathematica and I am getting some inconsistencies when I plot it. As I really need to understand were this comes from I would appreciate any help. I am working with a ...
10
votes
2answers
574 views

Restrict Locator to a certain graphic inside Manipulate

I would like to restrict the Locator inside Manipulate to a certain graphic. For example if I display two graphs, I would like to be able to click on the right one and use this information in other ...

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