3
votes
1answer
59 views

How to use the edge routing of LayeredDigraphEmbedding when specifying explicit vertex coordinates?

The "LayeredDigraphEmbedding" GraphLayout uses an edge routing algorithm which produces nice and readable diagrams and curved ...
1
vote
0answers
33 views

Solving non-linear coupled ODE with constraint using NDSolve

I am trying to use NDSolve in Mathematica to solve the following coupled ODEs from a paper I am trying to understand. I have the following 5 differential equations: ...
0
votes
0answers
39 views

Better chances on a gambling game [closed]

I'm working on a program that I hope it will help me to get better chances on a gambling game. I have a very large database of numbers how occur in this game and my program pass through those numbers ...
0
votes
1answer
57 views

Simplify an XMLObject by keeping only specific elements

I would like to extract from an XMLObject only the XMLElements with a specific tag. Inspired from the Mathematica help (section transforming XML, introduction, the example with the colours), I have ...
-3
votes
0answers
39 views

Harris corner detection and plots [closed]

Could someone help me recreate these plots using Mathmatica. https://youtu.be/9-F5-gUIAWE?t=20m28s The are applying a hessian matrix to an image, and calculates the eigenvector.. And They then ...
10
votes
0answers
132 views

Is FullGraphics an abandoned function? Is there an alternative?

FullGraphics hasn't worked entirely for a long time and the situation appears to be getting worse instead of better. In Mathematica 10.0 and 10.1 a simple usage ...
4
votes
1answer
48 views
0
votes
2answers
66 views

Martingale pricing_Simulation random walk stock price

I need to make an example of a walk of a stock price.I have this data: and i need to resolve this equation: where "W" is a Wiener process [0,Δt]. I need to make a path of 157 steps(date of ...
1
vote
0answers
22 views

How to make lines not wrapping in text-mode Mathematica? [duplicate]

When running Mathematica from Unix command line, i.e. pure text mode, the lines wrap at about 70 pr 80 characters, creating lots of visual clutter. How do I set it so that any outputs will not wrap ...
-1
votes
0answers
41 views

Partition In Cellular Automation

Since i am pretty much new to Mathematica, i am having trouble with the use of Partition in Cellular Automaton. The code,taken ...
-1
votes
0answers
37 views

how to check whether a variable contains a specific character [closed]

After assigning a string to a variable, I want to test whether this variable contains a specific character for subsequent treatment -- something like the following: ...
9
votes
2answers
129 views

How to align coordinate systems of Inset and enclosing Graphics?

Suppose we have some plot with AspectRatio not being Automatic: ...
-3
votes
0answers
47 views

Was this file created in mathematica? [closed]

Below is a link to the pdf file. (The tag I used is not accurate to my question, but I could not find a relevant tag). http://www.math.harvard.edu/~knill/teaching/math21a2011/21a_fall_2011.pdf
2
votes
2answers
81 views

Incompatibility of CountryData[] between v. 9.0 and 10.1

There seems to be an incompatibility between the representation in CountryData[] for versions 9.0 and 10.1. The documentation on ...
0
votes
1answer
47 views

Suppress attributes of all XMLElements of a XMLOBject [closed]

I woild lke to display a XMLOBject as a tree. The problem is that, in my XMLObject, I have some XMLElements which have big arguments. Consequently, I didn't manage to have a concise tree, easy to ...
6
votes
1answer
150 views

Using ImageIdentify

How long does it take ImageIdentify to give an answer for one image? Also, I suppose using it requires an Internet connection with Wolfram servers. Is that correct?
3
votes
4answers
280 views

How to plot frequency polygon?

I have data sample. Built and plotted histogram based on the sample. How can I plot frequency polygon now? That's example of the desired result. Here is code: ...
0
votes
0answers
71 views

Numericaly solve 3 coupled differential equations [closed]

I'm kinda new to mathematica and I was just trying to solve a system of 3 coupled 2nd order differential equations (for a 3 body under gravitational potential problem simulation). I'm using NDSolve, ...
4
votes
2answers
175 views

How can I plot histogram with the same number of values in every bin?

For example I have 100 values sample. I'd like to build histogram in which every bin contains, for example, 10 values. How can i do that? Thanks.
5
votes
0answers
53 views

Operator which can be interpreted as binary and unary

I'm a bit lost with the way how e.g. the + operator is implemented in Mathematica as binary (infix) and unary (prefix) operator depending on the context, since I would like to define a similiar ...
0
votes
1answer
57 views

NDSolve issue with initial and boundary conditions

While solving the heat equation in one spatial variable $u_t = u_{xx} $ (x goes from 0 to L) with the initial temperature distribution $T_0 \frac{x(L-x)}{L^2}$ , and with neumann boundary conditions ...
0
votes
0answers
46 views

“Real Graph example” to test algorithms

I wrote some algorithms which process graphs. I tested them and found those ones worked. But I would like to demonstrate them too. What is the best way to create example graphs from real world? I ask ...
0
votes
0answers
71 views

NIntegrate gives message NIntegrate::vars:

As seen in the code below, I initially constructed a list of functions of two variables ζ and t0. These functions are pure ...
10
votes
6answers
527 views

How to find all the positions of max value of a list efficiently?

For Example, list=RandomInteger[{1,100},2000]. Yes,I know Position[list,Max[list]] can do. But it's based on pattern ...
-3
votes
0answers
32 views

DynamicModule with count for more Checkboxes [closed]

I would like to have a DynamicModule that increase a counter once a checkbox is selected. This is my code, the problem is that now i can see only one checkbox. What am i doing wrong? Can anyone help ...
2
votes
1answer
78 views

Applying a function to a column of a dataset [closed]

Functions can easily be applied to columns of datasets, as in the documentation it is shown. Now I want to apply a function with parameters to a column, but I get a list rules. E.g. ...
0
votes
0answers
33 views

Series Expansion of Differential Operators [duplicate]

We know about the possibility of series expansion of a function in Mathematica. Same as below, where a function f[a x] is expanded around zero up to 5th order. ...
1
vote
1answer
57 views

Stream plotting in polar coordinates [duplicate]

I got to a scalar field that really looks just fine to me in polar coordinates. "looks just fine" = all the physical limits make sense. The scalar field in polar coordinates r and θ is: ...
9
votes
2answers
149 views

The envelope of a set of translated and rotated ellipses

I achieve a dynamic graphics by using Manipulate as follows: ...
5
votes
3answers
157 views

Constructing a grid from a matrix

I would like to construct a grid from a matrix. For example, one possible matrix is $M1$. $$M1= \begin{pmatrix} c2 & a1 & a1 & a1 & a1 & a1\\ a2 & b1 & c2 & a1 & ...
2
votes
1answer
50 views

Plot directional field with a initial vlue

I do not have enough reputation to comment on other questions, hence I have to ask my own one I want to solve the following nonlinear first order ODE, $$(1 + x) (0.5 y[x]^{-0.5} (x - y[x])^{0.5} - ...
5
votes
4answers
185 views

How to multiply lists of data?

Let two lists of data, say lst1={{x1,y1},{x2,y2},...,{xn,yn}} lst2={{x1,z1},{x2,z2},...,{xn,zn}} I need to construct a third list ...
5
votes
0answers
111 views

Incorporating photos into a Mathematica-made web page

I use Mathematica to make my web page. I make various .nb files, usually with photos, and then use an Export command to convert the .nb file to an .html file with ...
-2
votes
1answer
45 views

FindShortestPath does not work

The FindShortestPath doesn't work in this graph, can someone tel me what's wrong? ...
0
votes
0answers
41 views

Finding common roots to several functions

I am trying to solve the following problem. Given $a\in\mathbb R^n$, $u\in\mathbb{R}^n$, $m\in\mathbb{N}^\star$, Find the/some common roots $(t_1,...,t_m)$ of the $\frac{m(m-1)}{2}$ ...
2
votes
4answers
180 views

Print all numbers from a sequence which don't contain the digit 7

so i have this: Cases[RecurrenceTable[{a[n + 1] == 7 a[n] + n, a[1] == 1}, a, {n, 7}], Except[7]] But i noticed that it will only exclude numbers that are 7, and ...
0
votes
0answers
17 views

How can I keep a keystroke's variable change from making my dynamic eventhandler window inactive? [closed]

I press an arrow key like this: "RightArrowKeyDown" :> {message = "", code code code ... The message in my dynamic eventhandler window changes to nothing. ...
1
vote
2answers
56 views

Calculating Variance (without Variance expression)

I am learning Mathematica on the fly, one of my tasks is to find the variance of white noise. I followed the tutorial for finding white noise by using the code: ...
0
votes
1answer
21 views

Behavior of custom file chooser code changes when placed inside DynamicModule

My primary objective is to build a file chooser that aides a user in selecting files into one of two categories. Files can be individually selected, or based on the clicking of a specific checkbox, ...
2
votes
2answers
80 views

A peculiar behavior of NSolve[]

NSolve[Power[x + 1, x + 1] - Power[x, x + 2] == 0, x, Reals] returns: {{x -> 3.14104}} Great. However, ...
3
votes
1answer
91 views

Compute a hessian matrix on a image?

Is it possible for Mathmatica to load a gray image and apply a hessian matrix on it?... It used image processing to find good features.
0
votes
0answers
56 views

Using Fourier to return exponential function

I am trying to use Fourier to numerically demonstrate the following identity: $$ \frac{1}{2\pi}\int_{-\infty}^{\infty}\frac{e^{i\,s\,y}}{1 + a\,s}ds=e^{-y/a} $$ I'm getting the correct shapes, but my ...
1
vote
0answers
53 views

Orthogonality relations of Hermite polynomials

The Hermite polynomials are orthogonal. $$ \int_{-\infty}^\infty H_m(x) H_n(x) e^{-x^2}\, \mathrm{d}x = \sqrt{ \pi} 2^n n! \delta_{nm} $$ Does Mathematica not use this relationship? Because running ...
4
votes
2answers
100 views

Taylor series representation as an infinite sum

I want to see the Taylor series representation for arbitrary functions, e.g. $\sin$. With the Series[] command, I can only see the first $n$ terms. Is there the ...
0
votes
2answers
132 views

Projection of triangles onto a sphere

I am trying to find the solid angle taken up by a large set of triangles around a central point. I have normalized the vertices of the triangles to a unit sphere around the central point, But the ...
0
votes
1answer
40 views

symbol matrix calulation

I have question about matrix calculation. like $\mathbf{b}^{t}\Sigma \mathbf{b}$, where $\Sigma$ is 7 by 7 matrix, and $\mathbf{b}$ is vector of 7. and each element in the vector b or $\Sigma$ is ...
1
vote
3answers
48 views

how to create, print and use variables using a loop in Mathematica?

I want to create, print and be able to use (i.e. do symbolic operations) variables in Mathematica using a for loop or equivalent. So, I have a bunch of variables of this form: $$dS_i = -\beta_i ...
0
votes
0answers
34 views

Attributes of statistics functions

Do statistics functions have some kind of attribute which ignore non-number (Indeterminate, ComplexInfinity, calculation "errors") elements of a list?
0
votes
0answers
32 views

Error when using NDSolve in SIR model

I have the following code for a SIR model: ...

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