8
votes
1answer
401 views

What is a good coding style for setting and changing application level constants?

Background: Every application has user-definable constants. The Java language has the Properties class to handle them. Question: What is a good and re-usable coding style for setting and changing ...
8
votes
1answer
460 views

Locking a value when Manipulating variables

I'm trying to achieve something similar to Bret Victor's brilliant Scrubbing Calculator in Mathematica. By using Manipulate I'd like to change the values of the variables such that if I modify one ...
8
votes
1answer
1k views

Handling failed FindRoot calls

I want to handle FindRoot calls which did not converge (e.g "thrown" error message FindRoot::cvmit) ...
8
votes
5answers
384 views

How to distinguish between lists and values?

I have a (hopefully small) problem with some numerical integration algorithm, more specifically I want to integrate the imaginary part of a complex valued function, e.g. ...
8
votes
3answers
993 views

Efficient image Import

I have several sets of 20 images I need to import. Each time they have different categories. "Name"<>"Cat"<>"No" Electric B 1 for example. I need to create lists that contain the images ...
7
votes
1answer
96 views

How to convert arbitrary raw boxes directly into String?

This question is motivated by the recent question about searching inside of the NB files. According to the Documentation, ToString expects a high-level WL ...
7
votes
1answer
119 views

ToExpression and ToBoxes aren't inverses of each other?

Applying ToExpression and ToBoxes repeatedly to Hold[1/1] gives many ...
7
votes
1answer
78 views

Is it possible for librarylink function to be Listable like that in Compile? [closed]

We know in Compile, there is an Option RuntimeAttributes -> {Listable} which can let the compiled function easily explore the ...
7
votes
4answers
297 views

Dynamic Epicycles

Thanks to all the thorough answers and comments, I've written the following code, which builds a variable number of epicycles. However, when I apply the formula ...
7
votes
1answer
4k views

What is the difference between Mathematica and Matlab? [closed]

I am totally a beginner to Wolfram products and I'm searching for a software to solve my math problems with. Like this math problem that I've solved using $\LaTeX$ in ...
7
votes
3answers
382 views

FEM Solution desired for “Plate with orifice” deflection: Application of Boundary Conditions and use of Regions

I found the deflection of an orifice plate (circular plate with a hole) subject to uniform pressure using Mathematica's NDSolve functionality. The plate is fixed at its outer circumference and is ...
7
votes
2answers
115 views

How to make a notebook take action whenever a particular symbol is defined or redefined?

For teaching purposes, I want to create a Mathematica notebook that will "notice" when the user defines or redefines a variable or function of a particular name, so that it can check the value and ...
7
votes
2answers
395 views

How much time should one give Mathematica for an integral evaluation?

Sometimes when I do integrals in Mathematica (M), it keeps thinking and thinking and I have no idea what is going on inside M. For how long should one wait or how does one know whether M has not got ...
7
votes
6answers
681 views

How to draw a dodecahedron with each face modified to a pentagram?

I'd like to draw a dodecahedron with each face carved on the sides so it becomes a pentagram. I wonder how to start to do this kind of task in the Wolfram Language? Edit: The result should still be ...
7
votes
4answers
147 views

How to map Unevaluated over a list

I have a list {a1, a2, ...... , an}, in which all as have been initialized to a number. I want to get: ...
7
votes
2answers
306 views

How to make a binary function associative? (Or define an n-ary function?)

Suppose I have a simple function that I assign to an operator f[a_, b_] := a + b CirclePlus = f Then I want to write ...
7
votes
2answers
273 views

How can I construct a recursive pattern guard?

I am modelling binary trees in Wolfram Language by writing them as three-element lists, like so: binTree = {nodeVal, leftChild, rightChild}. It does not yet matter ...
7
votes
1answer
352 views

Computing launch parameters for hitting a point in 3D with projectile under influence of wind

The end goal of this problem is to compute functions which describe the launch parameters which are needed to hit a specified goal in 3D in the presence of wind disturbances. This is as far I have ...
7
votes
2answers
252 views

Apply ColorFunction to an Image [duplicate]

is there a faster way to change the colors of an image from grayscale to something like this: ...
7
votes
1answer
402 views

Poincaré map for dynamic billiard

There's a very nice demonstration of dynamic billiard written by Dan S. Reznik that can be found on demonstrations wolfram(along with the code): here I was thinking whether it would be possible to ...
7
votes
3answers
1k views

Suppress extrapolation of interpolating function in a ContourPlot

I have defined an interpolating function, myfcn[x], valid on the domain x = 0 to 1.5. I am then using ...
7
votes
2answers
536 views

A topoplot function for Mathematica

Matlab's EEGlab toolbox has a topoplot function: http://sccn.ucsd.edu/eeglab/ A typical topographical plot of an EEG signal is given below: How can I reproduce this in Mathematica. I know that ...
7
votes
1answer
326 views

Dataset and string conversion, using Internal`StringToDouble

i'm trying to get familiar with the new Dataset-stuff in Mathematica 10. As it will (hopefully) provide some benefit for me, I have started to convert my app to move from list and list of rules to ...
7
votes
1answer
528 views

Why Plot3D does not accept Epilog option

I am trying to visualize 3D points with Plot3D using the option Epilog. If you check the options of Plot3D ( Options[Plot3D] ), it can be seen that Epilog is one of ...
7
votes
2answers
257 views

Evaluation in lambda function

If I have a function, that returns a function, for example: f[a_] := a^2 * # & then f[3] == 3^2 # & Is there a way ...
7
votes
3answers
364 views

Where did I go wrong with my implementation of the trapezoidal rule?

One method for doing quadrature, called the trapezoidal rule, improves accuracy by connecting the points on the curve corresponding to the points of subdivision with line segments, forming trapezoidal ...
7
votes
1answer
952 views

Getting clearer StreamPlot output

When I do a StreamPlotof a rather complicated pair of differential equations, it loses some details. For example: ...
7
votes
2answers
1k views

Manipulating plot of random iterated function system fractal

I'm generating the Sierpinski Gasket by implementing a chaos game in Mathematica. What I'd like to do is create an interactive manipulation with a slider, whereby moving it forward, plots all the ...
7
votes
2answers
169 views

Making ColorSetter work like a PasteButton

I might be missing something obvious here. I am building a palette for constructing code to make certain graphics. The idea is that my colleagues can click buttons instead of having to know the right ...
7
votes
1answer
516 views

How to plot points with uncertainties and dates assigned?

I want to plot a graph from list of points, but each point also has uncertainty assigned AND date. Without uncertainties DateListPlot works great, without dates ErrorListPlot works OK, but how it ...
7
votes
3answers
390 views

How to rename a built-in function?

I want a built-in function renamed without loss of any properties, I want the shorter name to appear in all results and to be recognized as input. Is it possible?
7
votes
1answer
916 views

Placing Manipulate controls in multiple columns

I have a Manipulate construct with a square Graphic on the left side and all the controls placed on the right side. There are so ...
7
votes
2answers
9k views

Simple ways to evaluate a derivative at a point?

The contrast in behavior between, say, f[x_] = Sin[x^2]; f'[2] vs. u[x_, y_] = Cos[x + y^2]; has always bothered my ...
7
votes
1answer
212 views

Prevent interdependence of controls

My question is probably best illustrated with this small sample code: ...
7
votes
4answers
1k views

Mathematica gives wrong answer for an integral

When I execute the following, Integrate[ Exp[-w^2 + I w^3], {w, -∞, ∞}] I get (2 E^(2/27) BesselK[1/3, 2/27])/(3 Sqrt[3]) ...
7
votes
1answer
515 views

How to create a multi-selectable setterbar with colored buttons

Background: consider the following code-snippet. ...
7
votes
3answers
3k views

Animate ParametricPlot3D for two different parametric equations

I want to write a computer program to generate 3-D plots (with x-y-t axes) to demonstrate the evolution of the two missiles in the following case: i. $x = 100t$, $y = 80t-16t^2$ for $0\leq t\leq 5$ ...
7
votes
6answers
2k views

Simplifying nested If statements

Consider : list = {100,102,103,99,106,107,104,112} I want to consider, extract only the "big moves" of that time series. In this case the moves bigger then 5 ...
6
votes
2answers
296 views

Diagonals of a regular octagon

We had a little activity after school today and one of the questions was: All diagonals are drawn in a regular octagon. At how many distinct points in the interior of the octagon (not on the ...
6
votes
1answer
160 views

How does thing[“property”] syntax work?

Many builtin "things" support the (usually undocumented) syntax thing["property"], and usually the available properties can be listed using thing["Properties"] (thing["Methods"] might work too). ...
6
votes
2answers
424 views

Using Greek $\LaTeX$ fonts

I want to use the $\LaTeX$ font in graphics. For text/numbers, this is easily done by FontFamily -> "CMU Serif" (on Ubuntu) like this: ...
6
votes
4answers
320 views

Dynamic list in which the sum of the elements is invariant under changes to the elements

2nd Update Here's a snapshot of a graphical user interface I'm thinking. I hope this could be self-explanatory and demonstrate the functionalities I mentioned in the 1st update. Thank you all! ...
6
votes
2answers
422 views

How do I plot my country map with weather data stations?

I've tried this code, but I can't plot the coordinates in my country map. ...
6
votes
3answers
385 views

How can i construct a 3D surface pass through a curve defined by formula and some other controllable points?

For example, If a have a curve defined by x^2+y^2=1 and z=0, and some isolated points having z coordinates, Can I construct a 3D surface passed through? It's better if I can change the surface shape ...
6
votes
1answer
730 views

Collision detection algorithm (discrete) with sweep and prune algorithm

For a more complex collision detection approach, I need an efficient (aka fast) algorithm to prune the elements by using boundary boxes. A classical algorithm is the so called sweep and prune (SAP) ...
6
votes
3answers
332 views

How to use a compiled function in numerical optimization

I'm trying to wrap my head around function Compile. So, this is a spin-off question from: a previous question on using compile[] correctly. I have a function that ...
6
votes
2answers
171 views

DeleteMissing level spec confusion

Given: titanic = ExampleData[{"Dataset", "Titanic"}] Why does this correctly delete Missing[] elements: ...
6
votes
2answers
247 views

How to understand the process of ListCorrelate when it in two-dimensional condition?

Toady,I learn a function ListCorrelate,and I can understand process of execution his result in one-dimensional. However,the ...
6
votes
1answer
535 views

Parallel optimization of Markov Chain Monte Carlo

I'm trying to reduce the computation time of a MCMC simulation. Essentially I have a set of particles performing a random walk in a periodic random potential. The particles are independent and every ...

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