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2
votes
1answer
14 views

Unexpected CountourPlot behavior at corners

With Mma 12.0 on Win 10, I'm seeing an unexpected white line in the following ContourPlot. ...
4
votes
1answer
32 views

Removing Duplicates in List of Lists

I have in Mathematica a list of lists like this: ...
2
votes
1answer
23 views

How to follow symbolic links on disk?

In this question we learn that we can use FindFile to get the disk location of a package. However, I have some packages that are installed into my ...
1
vote
0answers
25 views

Mathematica Error Message Help [duplicate]

when using NMaximize[], I keep getting the following error message: Can someone please explain what <<99>> + <<86>> = 0 means?
1
vote
0answers
16 views

How can I generate a Poisson gap sampled list?

tstart = 0; tend = 3; num = 1024; tstep = (tend - tstart)/(num - 1); list = Table[i, {i, tstart, tend, tstep}] // N; Histogram[list] I have a list of 1024 points ...
-1
votes
0answers
24 views

Bivariate Gaussian Distribution [on hold]

The bivariate Gaussian curve appears as a mountain. I was just looking at it and then a thought came to my mind, Are there any points inside the mountain/3d object(Obviously we cannot see them) or all ...
1
vote
0answers
22 views

How to train custom objects using YOLO in Mathematica?

I want to train few custom object using YOLO V2 architecture but not sure how to do this. I know that with the NetTake and NetReplace, this is achievable. Can someone point out me in the right ...
0
votes
0answers
35 views

what code do I need to use for a step by step Gaussian eliminations and Cramer's Rule, with a 21x21 matrix?

I am trying to show step by step calculations by using mathematica calling wolfram alpha API and for some reason its interpreting as one number.` There are do matrices, matrix a is for the variable ...
0
votes
1answer
28 views

How I can obtain u and z?

Integrate[1/Sqrt(2*Cosh[y] - 2*Cosh[u]) , {y, z, u}] == 0.013 2*Cosh[z] - 2*Cosh[u] == 0.41 Can I obtain the parameters of u and z using above equations?
0
votes
0answers
17 views

Power Iteration Method Error

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1
vote
1answer
30 views

Printing Values Within a Function

Below is a function to calculate the overlap between two gaussian functions. ...
2
votes
1answer
41 views

Hammer projection to rectangular

This might be more of a mathematical problem than a Mathematica'l one, but still, maybe you'd help me. I want to write a function that would produce a rectangular image from an image with Hammer ...
1
vote
1answer
30 views

How to return the equal points between two lists

I have something like this ...
1
vote
0answers
25 views

How to make a StyleSheet with certain text in some cell types like Subsection, Subsubsection and alike?

I am modifying several StyleSheets to adapt them to convenient use at school. Now I am working on the StyleSheet for Mathematics classes. I would like to make several types of default headings on the ...
0
votes
0answers
11 views

How to make a StyleSheet with a custom-defined Cell type that will be open by default?

I am making a StyleSheet to conveniently use them for homeworks and class works in Mathematics classes. I base it on the JournalArticle StyleSheet. I would like to make it such that by Default opens ...
0
votes
0answers
35 views

probability of one sum greater than another sum [migrated]

There are two group of competitors, say, group A and group B. the members in group A are denoted as a1, a2, …, ai,.., aN; The members in group B are denoted as b1, b2, …, bi, …bN. Each member in ...
3
votes
1answer
34 views

Map list of functions over list of inputs

Given a list of functions {f1, f2, f3, ...} and list of inputs {1, 2, 3, ...} I wish to produce the list ...
0
votes
0answers
36 views

Calculating an eigenvector [on hold]

I was trying to reproduce the results of an exercise where they calculate the normal modes of oscillation. $\begin{pmatrix} \dfrac{d}{dt}C \\ \dfrac{d}{dt}C^{*} \end{pmatrix}= - \dfrac{1}{i} \...
1
vote
1answer
27 views

Translate formula boolean to variables expression

I need prepare simple parser for Boolean formula in format CNF: So we have some formula like: $$ F = (x_1 \lor x_2) \land (x_1 \lor \overline x_3) \land (x_2 \lor x_4) \land (\overline x_3 \lor \...
1
vote
0answers
36 views

Solar System N body Simulation

This is an N-Body simulation for the Sun and the following planetary bodies: Mercury, Venus,Earth,Mars,Jupiter,Saturn,Uranus,Neptune and Pluto. Initial Parameters ...
4
votes
1answer
64 views

Solving and plotting an SIR epidemiology model

Folks, please advise me about solving and plotting an SIR epidemiology model. The model is given by: ...
1
vote
0answers
29 views

Need help with understanding a question concerning the power iteration method [on hold]

I just need help understanding a question. I was given the question Use the power iteration method to estimate the spectral radius for (I - B A) given a tridiagonal coefficient matrix. Although,...
2
votes
1answer
28 views

RecurrenceTable: numercial exception

When I added vector b into expression, it returned with RecurrenceTable::excptn: Value {2/3,-(1/3),2/3,-(1/3)} is a numerical exception. ...
1
vote
1answer
23 views

Export a multidimensional array which contains numerics and symbols?

Lets say I have an array defined as: Array1 = ConstantArray[0, {1, 3, 3}]; Array1[[1, 1, 2]] = 5; Array1[[1, 1, 3]] = t; How could I export this array since it ...
1
vote
0answers
28 views

Cannot use RotateRight function to move points in plot forward

I have a plot of activity which is matched to degrees of crank angle on the x axis. I want to move the plot forward by 180 degrees in to work to have the peak occuring at the beginning of the cycle,...
0
votes
0answers
12 views

Convert the mesh produced by AceFEM to .msh file?

So the title says everything. I would like to export the mesh produced by AceFEM to gmesh so that I can use the mesh in another program. Is it possible? Has anyone done this before? Thanks in ...
2
votes
0answers
41 views

NDsolve for differential equations

Im attempting to use the NDSolve funtction to solve a coupled system of 2nd order differential equations. The differential equations are the for the acceleration of ...
3
votes
1answer
36 views

How to efficiently select positions of elements in a sublist

Apologies if this is an already answered question, I was unable to find anything until now. I believe the answer will be quite simple, I have just been stuck on it for a few days now. I have a large ...
1
vote
0answers
20 views

ListDensityPlot do not show the exact color [on hold]

I use ListDensityPlot to plot a density contour, but it has some wrong white color. How can I fix them?
1
vote
1answer
38 views

Computing RMSE (Root Mean Square Error)

I have the following data: ...
0
votes
0answers
59 views

Why is this code keep collapsing? It always let Mathmatica not respond even when the memory was 60% in use

Messages: Coordinate $CellContext` intersections[3] should be a pair of numbers, or a Scaled or Offset form. Coordinate $CellContext`intersections[Rational[-17, 10]] should be a pair of numbers, or ...
1
vote
1answer
51 views

Element-wise minimum of two matrices

I am trying to compare two identically-shaped matrices and select the minimum of the two. This is an extension of a past question: Element-wise max of two lists, except I have three nested lists. <...
1
vote
0answers
40 views

Generate a poisson gap sampled list

tstart = 0; tend = 3; num = 1024; tstep = (tend - tstart)/(num - 1); list = Table[i, {i, tstart, tend, tstep}] // N; Histogram[list] I need to generate a list of ...
1
vote
2answers
61 views
1
vote
0answers
34 views

Jacobi Matrix w/o dot product

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3
votes
1answer
46 views

Interpretation of a Code (Cases)

I have the following code, and have been asked to interpret it: Cases[{1, 3.1, 2/3, x, 3 + I, "Yellow"}, _Integer | _Rational | _Real] I tried to play around the ...
0
votes
0answers
27 views

Solving the slow diffusion equation with NDSolveValue

I was trying to solve the following slow diffusion equation $$u_t = \frac{\partial}{\partial x} \left(u \frac{\partial u}{\partial x} \right)$$ The boundary conditions are $u(t,-2)=u(t,2)=0$. The ...
1
vote
0answers
21 views

Difficult Eigenvalue Problem

I have an eigenvalue problem of the form: f''(x)+V(x,lambda)f(x)=0 with Dirichlet boundary conditions: f(a)=A f(b)=B The eigenvalues lambda are complex, so they have both a real and imaginary part. ...
1
vote
0answers
24 views

Nesting, Manipulate and TabView

I have a Demonstration that employs TabView to show three related but slightly different functions, each view having slightly different controls. I can make it work fine nesting Manipulate in each Tab ...
-4
votes
0answers
45 views
0
votes
1answer
27 views

How to find the Maximal Absolute Error?

I found this fit but I do not understand how to find the maximal absolute error nor do I understand what it is really. I do not see what it is I would compare, would it be ...
0
votes
0answers
41 views
1
vote
0answers
29 views

Is it possible to speed up SDE simulation?

Is it possible to speed up SDE simulation in Mathematica? I am simulating a large number of Heston processes that look like the following (note this code is only a slight modification of the ...
2
votes
1answer
102 views

N body simulation

Im trying to solve a 3 body problem consisting of the earth moon and sun. I'm wanting to show the earth orbiting the sun and the moon orbiting the earth as a result of the gravitational forces. Where ...
1
vote
0answers
31 views

ListDensityPlot and DensityPlot do not give the same results?

I am plotting the same function using ListDensityPlot and DensityPlot but the output is different! There are some points where ...
0
votes
1answer
71 views

How to solve transient 3D heat equation with robin boundary conditions

Good afternoon! I'm trying to solve the following heat equation: with the following boundary conditions and initial value: Nut I'm getting error while solving it with NDSolve: ...
1
vote
0answers
50 views

Formatting in *.m file

I have my own package (just a bunch of functions) in the *.m file, which I load using the Needs[] command. Everything works fine ...
2
votes
2answers
61 views

Labeling a plot point under the axis

This works well: Plot[x, {x, 0, 1}, Epilog -> Text[1/2, {1/2, 0.1}]] This doesn't (the "1/2" label is not visible): ...
2
votes
1answer
61 views

How to make a video from png images

I have a set of about 100 .png images representing the evolution of the system I am studying: how do I create a video out of these images with Mathematica?
1
vote
1answer
32 views

Part Assignment of variables with argument

I do not really understand why this: a = {1, 2, 3}; a[[1]] = 3; a {3,2,3} works as desired, but this does not: ...

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