12
votes
1answer
818 views

How to extract and replace submatrix of a doubly-periodic matrix?

How can I effectively extract and replace a rectangular subpart of a toroidal matrix, i.e. one where boundaries are connected at opposite ends? Since the submatrix can overhang the edges, a simple ...
12
votes
1answer
263 views

Does InterpolationOrder cause conflicts with PlotMarkers in ListPlot?

Bug introduced in 7.0 or earlier and persisting through 10.3.1 or later My code: ...
12
votes
2answers
710 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 ...
12
votes
3answers
290 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] ...
12
votes
2answers
643 views

Surprises simplifying simple polynomials

I came across some somewhat surprising behavior of Simplify today, on something very simple. Let's take two cubic polynomials that we know have the same value: ...
12
votes
2answers
846 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 ...
12
votes
3answers
4k views

Strategies for simplifying complicated expressions

I have a very complicated expression involving trigonometric functions, complex numbers etc. You may find it here as it is too long to be pasted here. You may also find a screenshot of it here. ...
11
votes
2answers
156 views

Lookup with default broken in Dataset

Given an Association, ...
11
votes
1answer
349 views

Does NRoots own an abstract counterpart? If not, can we write one?

We know when solving linear algebra equations, despite its abstract syntax, LinearSolve is much faster compared to Solve: ...
11
votes
1answer
814 views

Where to download the MathWorld package?

I was trying to run some notebook I downloaded from MathWorld, but lots of them need << MathWorld`Curves` I tried to google it , only to find this, but ...
11
votes
2answers
278 views

Boundary effect of Graphics3D object Tube[]

I draw a Graphics3D object of two tubes: Graphics3D[{Tube[{{-0.2, -1, 0}, {-0.2, 1, 0}}, 0.05], Tube[{{0, 0, -1}, {0, 0, 1}}, 0.05]}, Boxed -> False] And ...
11
votes
3answers
406 views

Find asymptotics of $\sum\limits_{i=0}^{n/3} 2^i \binom{n-i-1}{\frac{2n}{3}-1}$

I have an expression 2^n / Sum[ 2^i Binomial[ n - i - 1, 2n/3 - 1], { i, 0, n/3}] ...
11
votes
1answer
171 views

Functions returns Command Completion Output

Is there a function that returns the output as if you invoked Command Completion. To help clarify I am looking for a function that returns the Cell Data as if you invoked ...
11
votes
3answers
1k views

How can I visualize 6 square matrices as a cube?

I have six square matrices of the same dimensions in a list, for example: ...
11
votes
2answers
743 views

Convert Graph to Graphics

In Mathematica 9, a graph is returned as an object with head Graph: In[1]:= CompleteGraph[8] // Head Out[1]= Graph ...
11
votes
2answers
456 views

How can I make a cell that contains an image which can be shifted?

When you're looking at some help pages, they may have cells containing images which can be shifted within the cell by left-clicking and dragging the mouse. Here is a sample: ...
11
votes
1answer
1k views

Manipulate (Linux version of Mathematica)

I'm runnning Mathematica 9 on Ubuntu 11.10. After installing CDF player I still have problem (most of time) with Manipulate. Only way I'm able to change value of a ...
11
votes
1answer
939 views

NDSolve Differential Equation Error

I am trying to solve the following differential equation- ...
11
votes
2answers
306 views

Plotting a function, x = 1024

The function s12 = 1/(Log[2^x]*((7.537/(x^2)) + (30.148/((2 + x)^3)))) returns expected function values for ...
11
votes
2answers
934 views

Graphically representing error in a Riemann Sum

I am trying to graphically represent the error in a Riemann sum. My current code looks like: ...
11
votes
2answers
714 views

backward compatibility

When producing or enhancing code, it is tempting to use recent new primitives of Mathematica introduced in version 7 and 8, but for library code or in preparation or future version change in ...
11
votes
4answers
4k views

What is the cleanest way to prevent divide-by-zero warnings?

If I evaluate {1, 2, 3, 4}/{5, 6, 0, 8}, obviously I get one warning: ...
10
votes
3answers
467 views

How do you concatenate matrices? And how do you make block matrices?

This is pretty trivial to do in Matlab, but I have not seen a function for it in Mathematica. Here is how you can do it with Join and ...
10
votes
2answers
366 views

How do you submit an Input type of “file” using URLExecute?

I have to submit a form like as follows: <input type="file" name="jpgFile"> I can't seem to find any instructions on sending this in URLExecute. If I ...
10
votes
4answers
282 views

Handy / flexible directory tree operations

Is there any shorter / more handy / more flexible way to get directory tree as a nested Rules/Associations list? I tried to incorporate ...
10
votes
5answers
330 views

Function for a series of joined slopes

I need a function for a series of joined slopes and my solution feels a bit kludgy. Is there a better way? A list of pairs of transition points and slopes: ...
10
votes
2answers
244 views

Backslash commands in strings?

I discovered by playing around that Text[DisplayForm@SubscriptBox["\[Lambda]", "k"]] produces the same result as ...
10
votes
3answers
1k views

How to estimate the matrix condition number in the 2-Norm?

The Mathematica documentation says it is possible to estimate the matrix condition number in norms 1, 2, and ∞. But the 2-norm raises a message. This is an extract from reference documentation ...
10
votes
1answer
329 views

How does LocationTest choose its “AutomaticTest”?

Is there a way of determining how LocationTest chooses its "AutomaticTest"? Sometimes it's clear from the ...
10
votes
2answers
600 views

Why is ParallelMap way slower than Map

I recently tried to use ParallelMap instead of Map and to my surprise encountered that ...
10
votes
1answer
704 views

ParallelEvaluate for function minimization

Is there a parallelized version of a minimization routine available in Mathematica? The objective function is non-linear and the gradients have to be numerically computed. Every function evaluation ...
10
votes
2answers
390 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
2answers
422 views

Is there a “GrabHand” and “OpenHand” MouseAppearance in Mathematica?

MouseAppearance[Plot[Sin[x], {x, 0, 5}], "LinkHand"] Unfortunately I cannot get a screen grab to show the link hand but it is a cartoon hand with a finger ...
10
votes
1answer
218 views

Unexpected result from Flatten

Consider the following three evaluations involving Flatten: Flatten[f[f[f[x, y], 1, 2], f[x, y]], Infinity, f] f[x, y, 1, ...
10
votes
3answers
819 views

Forest plot with Mathematica 9

Does anyone have experience with or a package for the creation of forest plots in Mathematica 9? For instance for subgroup analyses of cox model or meta-analysis (e.g rmeta package in R)?
10
votes
1answer
925 views

Is my expression too complicated for FullSimplify or am I doing something wrong?

I have a messily defined function $v(h, w)$ with $h, w \in \mathbb{R}$ and with a removable singularity at $h=1/2$, and I am trying to prove some of its properties using Mathematica. In particular I ...
10
votes
3answers
727 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
342 views

Using Gather to rearrange my data

I have a list of elements: {{1, 2}, {1, 5}, {2, 6}, {3, 7}, {4, 8}, {5, 6}, {5, 9}, {9, 13}, {10,11}, {11, 12}, {11, 15}, {15, 16}} I have to divide it into ...
10
votes
2answers
663 views

HighlightGraph with different styles

I want to highlight two different directed paths on a graph with two different style. I am using the following two code snippets: ...
10
votes
2answers
367 views

Prevent text from wrapping in a notebook

By default in the Notebook interface the text wraps. Is it possible to prevent this wrapping?
10
votes
1answer
318 views

How to work around incorrect tooltips in plots exported to HTML

This is an issue that I always wanted to investigate but haven't gotten around to solving yet: The tooltips for contour lines in a plot like this can be very useful in the Notebook interface: ...
10
votes
1answer
234 views

Mouse gestures or keyboard shortcuts for navigating forward/backward in the documentation center

Is there any way to get gestures (e.g. trackpad- or Magic-Mouse-swiping left/right) to work for navigating forward and backward in the Mathematica help browser, particularly on a Mac? If not, what are ...
9
votes
3answers
295 views

Implementation of a matrix formula

For the Bézier surface, which owns the following matrix definition: $$\begin{align*} S(u,v)&=\sum_{i=0}^m \sum_{j=0}^n P_{i,j} B_{m,i}(u) B_{n,j}(v)\\ &=\small ...
9
votes
2answers
156 views

Passing an unevaluated part of an association to a function

I'm making a UI widget that controls sound volume on a speaker using a slider, e.g.: ...
9
votes
1answer
247 views

10.0.2 breaks a recursive “trie” query

The 10.0.2 Dataset type system complication breaks a recursive trie constructor that worked in 0.1: ...
9
votes
1answer
157 views

Tracking Initialization

How to track Initialization step by step? Any tricky solution is ok. One condition, x should be ...
9
votes
2answers
323 views

Any packages for vertex enumeration on Mathematica?

My work requires me to enumerate all vertices of a polytope defined by linear inequalities from time to time. And I'm mainly working with _Mathematica 9.0 on Mac OS X 10.9. So I wonder are there any ...
9
votes
3answers
195 views

Problem constructing Association tables with some operators

fixed in 10.0.2 First, set up the example Dataset from the documentation: titanic = ExampleData[{"Dataset", "Titanic"}]; ...
9
votes
1answer
547 views

Generating high quality charts in Mathematica for use in LaTeX and Word

I frequently have a probelem using my charts in reports because the text (axes labels and tick marks) look low resolution (fuzzy). When I export my charts, i export them as PNG files. Unless I'm ...
9
votes
2answers
317 views

Using Except with strings

Suppose that I have the following sample list, called list: list = {"bBb", "aAa", "aaa"}; Now suppose I want to select the ...

15 30 50 per page