0
votes
1answer
25 views

Is it the correct syntax with TransformedDistribution?

I define a function as f[x_] := ...;which is in fact the PDF of a random variable $X$. The PDF if given by $f_X(x)$. Let $Y$ is a random variable, which is the ...
1
vote
2answers
57 views

MMA gives error when a different PDF expression is used for the same distribution

I have the following MMA code. Note that the function I declared at the very beginning is the PDF of square of a Nakagami Distributed random variable. With $m=1$ and $P=1$, $f(h)$ becomes Exponential ...
-1
votes
1answer
159 views

Can Mathematica solve this integral numerically?

The PDF of $H$ is given by $f_H(h)=\frac{K+1}{\tau}\exp\left(-K-(K+1)h/\tau\right)I_0\left(\sqrt{4K(K+1)h/\tau}\right)$ Here $I_0$ is the 0-th order Bessel function of first kind
0
votes
1answer
60 views

Solving equations with change of variables is not working?

I want to express it in the form $$\text{expr=}\int_{-\infty}^{\infty}C_1\exp\left(-t^2\right)f(t)dt$$, i.e., the integrand is a bounded smooth function $f(t)$ times $\exp(-t^2)$ and the domain of ...
0
votes
1answer
125 views

Why MMA is not able to solve this problem?

I am running these following code in Mathematica. But, MMA does not output anything. It is giving me an message as "The integrand .... has evaluated to non-numerical values for all sampling points in ...
1
vote
1answer
143 views

How can I evaluate a certain probability density function?

The PDF of a random variable $X$ is given by Note that $H(t)$ is also a function of $x$. Here $-\infty<\mu<\infty$, $\lambda>=0$ and $m>=1/2$ Let $I$ be a function of random variable $Y$....
0
votes
0answers
13 views

How to create assignments to Overvector Programmatically

I wish to write a function that accepts to lists. One is a list of list, holding the components of a several vectors. Ex.: comp = {{a,b}, {c,d}}. The second list ...
50
votes
4answers
2k views

Changing color of an object in an image

Consider the following image: How can I change all red colors in this image into (for example) blue.
4
votes
0answers
56 views

Web Browsing Automation: how to expand all comments under a blog post?

I wish to expand all the comments under a LiveJournal post for the purposes of saving the complete thread of comments. According to LiveJournal's FAQ when a post gets more than 50 comments they are ...
-3
votes
0answers
22 views

Setting up teams to play in games

Imagine there are 12 teams, numbered 1 through 12. There are 10 games those teams can compete in, with two teams needed per game. There are 10 rounds, and it is important that after the 10 rounds are ...
0
votes
1answer
47 views

How do you manipulate this in 2D

Use Manipulate to create an interactive plot that shows the parametrically-defined curve described by {x[t], y[t]} = {t Sin[t], t^2/15} for ...
0
votes
0answers
16 views

Weird SeriesData behavior?

I was trying to calculate the determinant of a matrix whose elements are truncated series. As a result I obtained an expression like this: ...
11
votes
2answers
384 views

Create new notebook at fixed size

Using Ctrl+n we are effectively doing FrontEndTokenExecute["New"] and, at least on Windows, a new window has a WindowSize equal ...
0
votes
1answer
27 views

How to make the conjugate transpose

I have a problem to make the conjugate and transpose the matrix.May anyone help me please. ...
8
votes
1answer
74 views

Memory leak with NDSolve

This is not the first time the question in mentionned (cf in particular this recent question NDsolve memory leak), but there seems to be a serious issue of memory leak - or am I missing something? ...
3
votes
1answer
50 views

DSolve apparently returns wrong symbolic result

Bug introduced in 9.0 and persisting through 10.4.1 I am trying to get Mathematica to calculate the correct solution $x(t)$ of the following ODE: $\dot x = a x(t)+ct^n$ for $a>0$, $n\ge 1$, $c&...
0
votes
2answers
27 views

NSolve and domain specifications

I am using NSolve to find roots to a system of polynomials that describe some chemical reactions. However, I am seeing some odd behavior when I restrict the domain. First, the basic setup: ...
9
votes
2answers
2k views

How to make traditional output for derivatives

Hello again after some pause. i have a problem how to present partial derivatives in traditional form, not as Mathematica gave it to me in its notation. So I want to present this ...
1
vote
1answer
37 views

Plotting an equation describing a Joukowski airfoil

I am trying to plot an equation that will give me a Joukowski airfoil and am having trouble getting any results. The equation that I am using is as follows: ...
2
votes
0answers
288 views
+100

How to perform convolutions on this complicated pdf?

For a known pdf f[x], I need to calculate integrals over the probability density of the means of Logs[f[]] of independent samples from f[x]: $$Q[t,n]\equiv P(\frac{...
13
votes
1answer
349 views

Disconnected Frame/Axes in Plots

Is it possible to have "Tufte" style figure axes? That is so that the axes do not need to connect or span the entire data range? For an example of what I mean from the R's default histogram style: ...
5
votes
1answer
158 views
+50

Finite difference method not converging to correct steady state or conserving area?

I am working with the following PDE, which is an advection-diffusion type equation. It describes the movement of a fluid-fluid interface inside an annulus of inner radius $R_1$ and outer $R_2$ under ...
6
votes
2answers
222 views
+100

Symbolically prove that two expressions are identical

I encountered this problem when trying to reproduce the result of this paper. (The relevant parts are all included in the preview i.e. the 1st page of the article. This link is just given as ...
0
votes
2answers
38 views

Finding and plotting a parametric solution to a complicated equation (transcendental, log-polynomial)

I am trying (desperately) to find a way to solve a transcendental equation whose solution $x$ depends on non-numerical parameters $a$ and $b$. And then to produce a ...
1
vote
1answer
88 views

How to remove parts of an expression

I have an expression where terms Transpose[R].R appear. R is a matrix with the property Transpose[R].R=IdentityMatrix[3]. How ...
3
votes
1answer
104 views

Solve 3D Electric Field using FEA

The objective is to solve the 3D electric fields for the geometry below and generate the continuous function eField3D[x_,y_,z_]. The method I was planning on using ...
2
votes
2answers
228 views

GeoGraphics examples not running correctly

I'm trying to work with the new GeoGraphics functionality in Mathematica 10, starting with the example given here. None of the code seems to run well for me, though. I try to run the first command: <...
0
votes
0answers
21 views

Question on Poincare section example

I'm trying to make a Poincare section. On the Wolfram Documentation Center they give an example that includes the lines ...
-1
votes
1answer
51 views

Problem with a chemical optimization problem [on hold]

First of all, I want to say that I'm quite new to Mathematica. I searched a lot on this site to learn how to solve my problem, which this is the problem of my life! I want to minimize a function. It ...
0
votes
0answers
28 views

Removing 1 from FactorInteger

I am trying to remove the factor of 1 out of FactorInteger, so that I can search though numbers with common factors easier. Here is what I have already: For[n = 0, n < 10, n++; b = FactorInteger[...
1
vote
0answers
29 views

Is there a Wikidata - based Entity system yet?

Wikidata.org seems to have a similar goal as the new Entity/EntityProperty Wolfram-knowledge base system. The differences are that Wikidata is open, promising faster expansion and fixing, but of ...
0
votes
2answers
70 views

Plotting the solution of a Chini differential equation

In DIFFERENTIAL EQUATION SOLVING WITH DSOLVE by D. Kapadia, there is a Chini differential equation : sol = DSolve[x'[t] == 5 x[t]^4 + 3 x[t]^(-4/3), x[t], t] ...
0
votes
0answers
17 views

Changing font size and style in VectorDensityPlot

I have this: VectorDensityPlot[{x, -y}, {x, -5, 5}, {y, -5, 5}, PlotLegends -> Automatic] and want to: 1) Add a label to the column bar legend on the side ...
4
votes
0answers
19 views

How can I move he documentation to another location after install on Windows?

How can I move he documentation to another location after install on Windows? I would like to move the documentation to another partition on my Windows filesystem. Michael Hale in chat recommended ...
2
votes
0answers
44 views

Simplifying integer inequalities to equality

I try (in Mathematica 10) FullSimplify[l >= l1 + l2, {l <= l1 + l2, Element[l | l1 | l2, Integers]}] But that gives back ...
0
votes
1answer
32 views

Working with WolframCloud

I'm using WolframCloud from my smartphone and I'm having trouble to select all the cells of my notebook to delete them. There is a command that selects all the cells in a notebook? I tried using the ...
0
votes
0answers
56 views

Pointers in Mathematica

Does Mathematica entertain Pointers in wolfram? I have a matrix and I want to make function At such that At(MatrixName,row,col) = NewValue I am able to update the ...
0
votes
0answers
37 views

Fourier Transform for Blazed Fork Grating

I built blazed fork grating on Mathematica and the idea of using blazed fork grating instead of normal one is to eliminate the other diffracted order. So the blazed fork grating will let only the 1st ...
1
vote
1answer
142 views

How to confirm that computation uses multiple CPUs?

I have a multi-cpu machine, as shown below: ...
19
votes
5answers
355 views

Distributing function arguments with function compositions. How to compute $(f + g^2)(x) = f(x) + g(x)^2$?

Suppose I have two functions f and g. To compute $f + g$ evaluated at a point $x$, I know that one can use ...
0
votes
0answers
35 views

Why isn't LowPassFilter working for these parameters?

First I define a function, just a sum of a few sin waves at different angular frequencies: ...
2
votes
0answers
21 views

ContourPlot with custom ColorFunction: Odd behavior of “Contours” option?

I am trying to generate a blue-cyan-green-yellow-red color gradient that is linear in Hue. The code ...
0
votes
0answers
14 views

Import[] .obj data with per-vertex colors?

There's a somewhat standard way of including per-vetex color with obj files: Geometric Vertex[edit] A vertex can be specified in a line starting with the letter "v". That is followed by (x,y,z[,...
0
votes
2answers
82 views

How to generate a Markov Matrix efficiently

A Markov Matrix is a square matrix,which have two features: All elements great than or equal to $0$(But I hope all element great than or equal to $0.1$) All the columns add up to $1$ I have a ...
1
vote
0answers
37 views

Remove columns basing on binary sequence

Possibly it is duplicate, still I could not find here elegant way to remove matrix columns basing on binary sequence. i.e. if I apply {1,1,0,0,1,0,1} to matrix it should delete columns 3,4 and 6.
4
votes
1answer
33 views

How to speed up NIntegrate when using an interpolating function output from NDEigensystem?

I have been working with NDEigensystem in order to find the resonant frequencies of different shaped drums. I would also like the coefficients of the different eigenfunctions so that each of these ...
1
vote
1answer
175 views

My code uses `ClebschGordan` but `Mathematica` is using `ThreeJSymbol`

I'm using a function that calculate CG coefficients with the function ClebschGordan but instead, I've got the following error because Mathematica is using ...
5
votes
7answers
426 views

how to get $n$ equidistributed points on the unit sphere

We can get $n$ equidistributed points in the unit circle using CirclePoints. But how do you get $n$ equidistributed points on the unit sphere(surface of a ball)? ...
0
votes
0answers
31 views

Running complex functions in parallel

I've got a module containing a loop and multiple calls to other functions, i.e. ...
24
votes
2answers
426 views

How to implement custom integration rules for use by NIntegrate?

How can NIntegrate be extended with custom implementation of integration rules? This answer of the question "Monte Carlo integration with random numbers generated ...

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