The tag has no wiki summary.

learn more… | top users | synonyms

2
votes
0answers
30 views

How to program efficient undershoot/overshoot

I would like to solve the following boundary value problem for $y(x)$ for a fixed value of $k$ between $0 < k <1$: $$y'' + \frac{3}{x} y' - y + \frac{3}{2}y^2 - \frac{k}{2}y^3=0 \\ y'(0) = ...
0
votes
0answers
29 views

Plot of Complex function of two variables

$f(u,v)=\frac{\alpha u}{1+v}$ is a function from $\mathbf{C}^2$ to $\mathbf{C}$. How to plot this function in Mathematica?
-1
votes
0answers
36 views

NDSolve second order differential equation with boundary condition [closed]

i have revised my codes several times but i dont get what is wrong. after running it i keep getting dis message ...
0
votes
1answer
35 views

How to get the dynamic expression

$$Z_{n+1}=\frac{\alpha Z_n}{1+Z_{n-1}}$$ How to write the above expression in Mathematica? I want to get say Z_100, Z_10 by that scheme. Can I call say $Z_{10}$ if $Z_{n+1}$ is given?
4
votes
1answer
92 views

Lyapunov exponent plot

I am trying to create a Lyapunov exponent plot as a function of $\alpha$ for two functions: $$ f(x) = (\alpha + 1)x - \alpha x^{3} $$ and a piecewise function given by following Mathematica code: ...
2
votes
1answer
117 views

Bifurcation diagram for Piecewise function

At the moment I am trying to create a bifurcation diagram of the discontinuous piecewise function given by following Mathematica code: ...
0
votes
1answer
73 views

How do I find the nearest city out of a list of cities?

I am trying to find the next closest city to city 1 and want to use a certain radius to check what is the closest city I'm trying to create an algorithm for a TSP. Does anyone know how to implement ...
-1
votes
1answer
76 views

Trying to write my own Greedy/ Nearest Neighbor Algorithm

So I'm trying to write my own function and compare it to the results I have from using FindShortestTour. Does anyone know how to find the distance from each city to each of the others without ...
1
vote
1answer
66 views

How would I go about simulating conditional random birth 100 times?

So I have the following scenario: Assume you have this organism that reproduces by itself. An organism either reproduces 0, 1, 2, or 3 organisms at a time. Assume they're asexual and reproduce only ...
0
votes
1answer
36 views

Kronecker Delta and Contraction in Feyncalc

I am trying to simplify a rather complicated equation involving vectors and kronecker delta. I am trying to use Feyncalc for this purpose, but somehow i am not able to do it using Contract/Trick. ...
7
votes
3answers
274 views

Calculating average distance between maxima

I'm having trouble figuring out a way to analyze some simple data. When graphed, the data I have make a somewhat sinusoidal curve. What I want to do is to find the x-values of the maximum peaks of the ...
1
vote
1answer
40 views

Adding extinction factor to Monte Carlo analysis

I'm looking to add an absorption component to this monte carlo analysis, essentially i want there to be a 1% chance that a photon gets absorbed at each event as it travels through the medium, once the ...
2
votes
1answer
107 views

3D Vicsek Fractal Notebook

Can I get a link to a notebook that explores this fractal structure? I am specifically asking for a url to a Mathematica notebook that generates and / or visualizes this type of fractal. If that ...
3
votes
2answers
195 views

How to set up a simple Monte Carlo Simulation

there is a 1% chance that there will be a scattering event, if there is a scattering event the direction of scattering will be determined by a random sample of the custom[a_] function and if there is ...
1
vote
2answers
125 views

A cone being intercepted by a slanted plane

I have the 3d cone: Plot3D[-Sqrt[x^2 + y^2], {x, -20, 20}, {y, -20, 20}, Mesh -> None, BoxRatios -> {1, 1, 1}] I need a slanted plane intersecting it. ...
1
vote
0answers
57 views

Implementation of Lubaehevsky-Stillinger Algorithm to pack hard spheres

To generate a model of a polycrystalline material with specified grain size distribution (e.g coming from a Monte Carlo Grain Growth simulation) the Paper "Effects of grain size distribution and ...
15
votes
5answers
3k views

3D surface that looks like a virus

I have been recently using Mathematica for composing animations that are part of the supplementary information of my papers. I am currently trying to build an animation that involves a viral ...
3
votes
3answers
171 views

Code for (a,b) with gcd(a,b)=1?

I am trying to make a big table that includes all ordered pairs (a,b) with a (1,2) (1,3) (2,3) (1,4) (3,4) (1,5) (2,5) (3,5) (4,5) (1,6) (5,6) ... Any ideas? Thanks!
0
votes
2answers
55 views

How to stop code from evaluating same thing twice?

I have this code for evaluating some fractions: ...
0
votes
1answer
34 views

Output form of a result [closed]

Suppose I computed something with Mathematica, and the result is in the form Gamma[1 + N]^2 How can I tell Mathematica to write the result in a more ...
2
votes
1answer
113 views

How to make hollow Graphics3D?

I keep seeing a notebook to use of Mathematica as a 3D Printing tool (e.g.: this link). In the notebook on slide 8/11, we find these pictures: I'd like to design it as such that, but I don't ...
5
votes
4answers
152 views

Functional way to Climb an Association Decision Tree

Associations are nice tool to create decision trees. Here is a toy example of how I'm starting to use it: ...
1
vote
1answer
256 views

How to implement the directed Barabasi-Albert algorithm in Mathematica?

Does anyone know how to implement an efficient version of the [directed Barabasi-Albert algorithm][1] in Mathematica that scales until hundred of thousands nodes? The directed network mechanism is ...
0
votes
0answers
63 views

Locating Periodic Orbits - Part II

In a previous post Part I I asked how could I locate the x0 position of a periodic orbit. I got only one possible solution but it does not work as I want. Let me be ...
3
votes
0answers
76 views

Is there a way to do a symbolic PLUR decomposition of a matrix?

I am looking for a way to achieve the PLUR decomposition of a maitrx, as given in this paper here. The equivalent syntax in Maple is: ...
1
vote
1answer
217 views

Getting code from the Wolfram Demonstrations Projects [closed]

I saw from mathematica's website, there is a fantastic project about the 2D Riemann Sum. Riemann Sums For Functions of Two Variables I want to see the similar effect in my Mathematica (with ...
0
votes
1answer
101 views

Sum Over Multiple Indices part 2 [duplicate]

Recently I asked this question as I was trying to see how to write a particular Identity. I asked about how to write the following sum: ...
1
vote
2answers
322 views

Sum over multiple indices

I would like to be able to enter the following left hand side of an identity. I can write the right hand side (i think) but am not sure about the left. The Left hand side is ...
1
vote
2answers
152 views

DSolve bvlim error due to Boundary condition at infinity

I am solving an Ode using Mathematica that has boundary condition at infinity which is why Mathematica is showing error message. Please help to tackle this problem. ...
3
votes
1answer
207 views

How to create a Poincare disk type kaleidoscope in Mathematica?

Creating a Kaleidoscope in Mathematica is not a new topic at all, examples can be found from the links like: Wolfram reference and Wolfram demonstrations. My question is how to create Poincare disk ...
1
vote
3answers
86 views

How to distribute but skipping one level

I would like to write a Rule that mimics built-in Distribute[], but one that distributes ...
0
votes
2answers
73 views

How do I tell pattern searcher the order in which to search for patterns given in general form?

I have a really long sequence of Symbols inside a function, say nonCommute[a,b,c,e,e,f,g,b,i,j], and I am implementing a ...
2
votes
1answer
54 views

Searching for symbol except within subexpressions with a particular Head

I would like to write a searcher like FreeQ that looks for a Symbol (or Head) in an ...
48
votes
1answer
1k views

DumpsterDoofus's captivating generative art

How can I render these beautiful images that DumpsterDoofus posted?
1
vote
0answers
62 views

Solving System of Equations that are made up of variables

I have a few questions as to how to write some parts of this code. Say I chose, n=1 Then it creates two vectors ...
4
votes
3answers
542 views

computing gaussian curvature

Can gaussian curvature K be computed from WolframAlpha or any other available Mathematica ...
18
votes
2answers
1k views

How to build a bvh (a motion capture file format) player in Mathematica?

How to build a bvh player that can be used to visualize human motions in Mathematica? Any idea or sample code would be appreciated. ...
0
votes
0answers
110 views

Converting code from Matlab to Mathematica [duplicate]

I have the following piece of code: ...
2
votes
6answers
166 views

Setting the elements of a list equal to elements of a different list

A = {a,b,c,d,e,f,g,h} B = {1,2,3,4,5} How would I go about setting some of the elements in list A equal to the elements in list B and then the left over elements ...
4
votes
3answers
125 views

Help with coding triangular nodes/elements

I'm trying to write a program where it will shoot out the triangle node numbers. For example, in the picture, if we choose to divide this triangle by 5 points, then the program will return out the ...
14
votes
2answers
955 views

Convert spectral distribution to RGB color

Presume I have a spectrum as a function of wavelength (an example being the blackbody spectrum): I want to convert that to a single RGB color to display on-screen, i.e. the "color" of that object ...
5
votes
2answers
312 views
7
votes
1answer
282 views

How to generate nonperiodic tilings?

I need to generate nonperiodic tilings which are similar to the attached figure (kite-domino tiling). I was thinking the code is similar to the code for the Penrose tiling. However, that code is too ...
0
votes
1answer
45 views

Any code to add elements of a list to make a new list? [closed]

Is there any code built in to add the numbers in a list sequentially? For example, lets say I have a list B. B has 6 numbers like below. B={0,6,5,4,3,2} I ...
2
votes
0answers
74 views

Linearised Einstein equations

I need to compute the linearised Einstein Equations around a fixed metric $g_{μν}=\text{Minkowski metric} + h_{μν}$, which is not the flat metric. Does anyone know a Mathematica package or a review ...
6
votes
2answers
677 views

Distribution of 10 points within a unit square

Related to some packing problems, following problem arose: Distribute 10 points within a square of sides 1, so that minimal distance between them is maximized. With the help of random simulation, or ...
1
vote
0answers
73 views

Solving for a charge distribution from a dipole moment [closed]

I've been looking around but I haven't been able to find any way of solving this conceptually simple problem. In short I am trying to find the charge density in a dielectric in an external electric ...
0
votes
1answer
204 views

curve on the surface [closed]

I have a bezier polygon aa=Table[{i^2.5, 2*Sqrt[i]}, {i, 1, 5}],is anyone can give me a example in Mathematica code that how to create another iso parametric curve on this bezier surface?Display the ...
0
votes
1answer
574 views

Use de Casteljau algorithm to create Bezier Curve in Mathematica [closed]

Is anyone can tell me how to create Bezier Curve with given Bezier polygon and parameter t by using de Casteljau algorithm (not the Bezier function in Mathematica)in Mathematica code? Thanks a lot!
23
votes
4answers
3k views

How to create effect like Van Gogh's stroke brush?

I need to apply Van Gogh's stroke brush effect to a random image Take the following image as an example: Thank you so much if you could help!