13
votes
4answers
714 views

How to automate a FrontEnd return?

I use some custom shortcut keys in KeyEventTranslations.tr. One is for the Delete All Output function: ...
7
votes
2answers
1k views

Creating Plots for a Family of Solutions

I am wondering how do you set the parameters appropriately for $a_n,\,\alpha,\,\text{and }b_n$ to plot the family of solution of: $u_n(r,t) = [a_n\cos(k_n\alpha t)+b_n\sin(k_n\alpha t)]J_0(k_nr)$ ...
15
votes
1answer
274 views

How to make a function like Set, but with a Block construct for the pattern names

How can we define a function that works like f[x_]=ComputeSomething[x] and treats x as a variable that does not have a value? ...
17
votes
5answers
4k views

How do I plot a plane EM wave?

I would like to display an electromagnetic (EM) wave. I have written code that works, but it does not "shade" the area between the graph and the axes. Both the ...
13
votes
2answers
996 views

Keeping Text Size the Same Throughout Entire Notebook File

Is there a way in which when you choose to format the size of the font within your notebook, for a particular cell, when you go into another cell, the default size font (12pt) will not be ...
0
votes
1answer
362 views

Symbolic Optimisation

I'm trying to solve symbolically the following optimisation: $$ \min_{q_uu}\ \Biggl[ q_u q_{uu}\psi B_{uu} + q_u q_{ud}\psi B_{ud} + q_d q_{du}\psi B_{ud} + q_d q_{dd}\psi B_{dd} $$ $$ + ...
3
votes
3answers
5k views

Product of elements within a list

Please Consider : list={{5,2,6},{2,8,3}} I need to get the product of all the element within list : As of now I do this : ...
22
votes
1answer
991 views

Using .NET 4.0 from NETLink

Using Mathematica 8, I can check the version of the .NET framework used by NETLink as follows: ...
16
votes
2answers
4k views

Delete the current notebook cell using the keyboard

Is there another way than pressing Ctrl+. until the whole cell is selected and then pressing Del? If this is not built in, can I create some sort of a global macro to do this and bind it to a ...
8
votes
1answer
740 views

Hankel Transform integrals won't work in Mathematica

I'm trying to do this integral, which is shown on the Wikipedia page on the Hankel transformation: $$\int_0^{2\pi}\mathrm d\varphi\;e^{\mathrm im\varphi}e^{\mathrm ikr\cos(\varphi)}$$ The answer is ...
39
votes
4answers
6k views

How do I save a variable or function definition to a file?

Is it possible to save a function which was created via Interpolation of some data in such a way that I can use this function in a new Mathematica session without ...
12
votes
2answers
734 views

Is it possible to use the LevenbergMarquardt algorithm for fitting a black-box residual function?

I have a black-box multiargument multiparametric function of the type SRD[dataPoint_List,params_List] which accepts experimental data along with the parameters of ...
114
votes
2answers
5k views

Implementing efficient multiple undo

At the time this question was asked, version 10 was not out yet. The Front End of Mathematica 10 does have multiple undo, see the answer by John Fultz. The Mathematica Front End's built-in Undo ...
24
votes
0answers
525 views

Changing FrontEnd automatic scrolling in version 8

In Mathematica versions < 8, the FrontEnd has a very intelligent behavior: On evaluation, it by default automatically scrolls down the Notebook window to the last printed Output cell but also ...
10
votes
1answer
300 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: ...
5
votes
5answers
2k views

Using implicit differentiation to find a line that is tangent to a curve at a point

A few days ago I asked about using differentiation to find a line that is tangent to a curve at a given point. J.M. provided a very elegant way to solve these kinds of problems in Mathematica. Now ...
11
votes
2answers
273 views

How can you stop ordering of InputField entries?

I have: InputField[Dynamic[d]] Dynamic[d] If I enter e.g. a b x^5 h m the entry automatically gets sorted, as per screen ...
16
votes
2answers
1k views

How can I change the keyboard shortcut for switching the active window?

The default keyboard shortcut (on Windows at least) for switching focus to the next window is Ctrl+F6, and for switching to the previous windows it's Shift+Ctrl+F6. How can I change this to Ctrl+Tab ...
4
votes
1answer
443 views

Get the neighboring vertices and incident edges from a vertex in a graph

I need to get the neighboring vertices and incident edges from a vertex in a graph. I assume NeighborhoodVertices can be used for the former. Anything better? Or ...
3
votes
1answer
908 views

How to write a function to add edges or vertex to a graph

I need to add either a vertex or an edge to a graph, and also sometimes, vertices or edges, or a mixture of the two. How to write a function for this?
16
votes
2answers
772 views

Efficiently collecting results inside a compiled function

When we don't know the number of results that will be generated, the usual way to collect results is Reap/Sow. Another ...
41
votes
8answers
2k views

Injecting a sequence of expressions into a held expression

Consider the following toy example: Hold[{1, 2, x}] /. x -> Sequence[3, 4] It will give Hold[{1, 2, Sequence[3, 4]}] ...
15
votes
3answers
645 views

Measure a DensityHistogram[] pair similarity

I study human vision and more specifically eye-movements. "If we display 2 symmetrical patterns (20 min one after the other), will our gaze distribution be symmetric is my research question." The 2 ...
24
votes
7answers
1k views

How to Derive Tuples Without Replacement

Given a couple of lists like a={1,2,3,4,6} and b={2,3,4,6,9} I can use the built-in Mathematica symbol ...
10
votes
2answers
346 views

Visualizing several long lists of numerical information to see relative frequency

Mathematica has very powerful visualization techniques. However, I'm at a loss at how to best make the following chart readable. ...
14
votes
4answers
1k views

What is the fastest way to locate an image inside a larger image?

let b = let c = How to do: find[c,b] that returns the bounding box of c in b? ...
10
votes
3answers
973 views

Passing down arguments

In R, one can use ... to pass arguments down to another function. For example ...
55
votes
6answers
9k views
15
votes
4answers
6k views

Using FindFit to fit $a\,b^t$: how to avoid introducing complex numbers?

I'd like to find a model $f(t)=a\,b^t$ which matches the following data ...
24
votes
3answers
1k views

Calling IronPython code from Mathematica

I'd like to call some IronPython code from Mathematica using .NET/Link. The problem is that the code lives in .py files, yet from Mathematica I can only load .NET assemblies which are DLLs. So it ...
4
votes
3answers
246 views

Transform vector with lag

Say I have a vector $Z_n$ with and I want to transform it into another vector using this formula: $X_t=Z_t+0.7Z_{t-2}$ The problem is that I am not quite sure how to get that $t-2$ lag in there. I ...
17
votes
2answers
2k views

List of Parallelize[]-able functions

The question is clear and is inspired by this question and the first comment on this question. Although there are many tricks for parallelizing things that are not ...
6
votes
2answers
409 views

Rectangle with rounded edges

Inspired from : Fit an image within a Rectangle [] in Graphics I would like now to fit an image within a Rectangle[] with rounded edges as shown in the example below : Is it possible ?
6
votes
1answer
749 views

Efficiency of ParallelDo when a global variable./matrix is being updated

(Disclaimer: I realize that the addition of matrices a and b below can be done very fast just by typing a+b. The code below is just meant to illustrate behavior similar to what I observe in much more ...
9
votes
2answers
1k views

RootSearch for complex or multiple equations

First the background. I'm trying to solve for the roots of a rather messy complex equation. This is not the exact equation, but it's a decent (simpler) stand in: ...
10
votes
1answer
1k views

Where can I permanently modify $Path?

I've quite forgotten: what file does one modify in order to add directories to $Path globally? Specifically, I want to include ...
8
votes
1answer
615 views

Is there any automatic differentiation package?

I'm wondering if an automatic differentiation package exists for Mathematica. This is what I mean by automatic differentiation.
7
votes
3answers
449 views

RecurrenceTable not evaluated: mathematica just echoes input

Forgive the newbie question... I am trying to create a table of the following system, following the Stirling example in the documentation, but Mathematica just echoes my input. What am I doing wrong? ...
18
votes
1answer
743 views

Module vs DynamicModule for a dynamic variables in a grid. || Spelling Bee

When my daughter asked me help with her spelling homework, for me the obvious thing to do was to write a Mathematica program for it. The words: ...
4
votes
2answers
583 views

How to add fill color to a 2D Graphics object?

Problem / background: consider the following code snippet. ...
3
votes
1answer
283 views

Result of Reduce contains duplicate terms

On my system, the result of this: f[x_] := 2 Sin[x] + Sin[x]^2; Reduce[f'[x] == 0, x] contains the following expression twice: ...
17
votes
3answers
7k views

adding labels to points in ListPlot

Table[{Re[5 Exp[I 5/2 t]], Im[5 Exp[I 5/2 t]]}, {t, 0, 6}] ListPlot[%] This code plots 6 points in the complex plane. To each point I would like to add a label in ...
16
votes
1answer
402 views

Convert GraphPlot[]s with many nodes into something that's human-understandable

This is more of an abstract/creative problem. I think everyone who has played around with GraphPlot, ended up with an image that looks like this, at least once in ...
6
votes
2answers
499 views

Text[] using Graphics

...
3
votes
2answers
206 views

ScientificForm is not being applied

I am looking to compute the value of $\sum^{3249}_{n=58} 2^{n \choose 2}$, but when I try to execute ScientificForm[Sum[2^Binomial[n, 2], {n, 58, 3249}]], I get a ...
10
votes
2answers
4k views

Equation of a line that is tangent to a curve at point

A common problem in the derivative section of calculus texts is "find the equation of the line that is tangent to the curve $y = \ldots$ at the point $P$." To find the line that is tangent to $y = 2 ...
52
votes
4answers
3k views

Using a PatternTest versus a Condition for pattern matching

My last question to the site resulted in several answers that involve using pattern matching in Mathematica, a feature I wasn't very familiar with at the time. I am currently reading Mathematica ...
11
votes
3answers
1k views

Can Eigenvalues[] and Eigenvectors[] be assumed to return the same ordering?

If I do back to back calls of Eigenvalues[] and Eigenvectors[] can these be assumed to order the values and vectors the same, or ...
10
votes
3answers
877 views

How to plot layered graphs?

Given a directed acyclic graph, there is always a possibility to plot the graph as layers, where nodes always send edges into one direction (usually down), to successive layers, and never backwards. ...
12
votes
5answers
840 views

define a function from a list

I would like to create a mapping from a list and I am wondering if there is a slick way of doing it. For example, consider the list ...

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