0
votes
0answers
5 views

Crash after long GroebnerBasis calculation

I am running a long computation of a GröbnerBasis and after some hours the kernel crashes. The memory usage increases enormous, and it crashes, when it reaches somewhat 4 GB RES, however it is ...
0
votes
0answers
5 views

Is there a way to make links to functions in a notebook?

Frequently I'm working on a function that's at the top of my notebook in a "functions" section, but I'm looking at the output of it in a lower "body" section of the notebook. When I want to edit the ...
0
votes
0answers
10 views

Cauchy Principal Value

Cauchy principal value of the following integration gives nothing in Mathematica. $\int\limits_{-\infty}^\infty\frac{\text{dx}}{x-2}$ I tried some hand calculation which is ...
0
votes
1answer
16 views

Asymptotic Radial Wave Equation

I'm trying to reproduce the following solution to the ODE, $$\frac{d^{2}u}{d\rho^{2}} = \frac{l*(l+1)}{\rho^{2}}u$$ Solution: $$u\left(\rho\right) = C\rho^{l+1}+D\rho^{-l}$$ What I've tried in ...
0
votes
0answers
11 views

Limitation of MMA in solving complicated functions?

I try to solve nonlinear PDE functions with NDsolve and NDIntegrate in MMA. And it seems that MMA will not work if the functions become too complicated. I do not know why. Below are my codes which ...
0
votes
1answer
36 views

Writing Faster Mathematica Code - Sow and Reap?

I am applying Select function to a large list called xyCoordinateCentreCircle. The dimensions of the list are: ...
0
votes
0answers
21 views

Export many lists without using loops

I have a Mathematica function that creates a RandomWalk chain of length l, by generating random points on the unit sphere and ...
0
votes
0answers
16 views

Filtering in frequency domain

I'm trying to modify a transfer function in the frequency domain by filtering it with a Butterworth filter. For example, let's say my transfer function is of the form : ...
0
votes
1answer
19 views

Setting the value of a list item

I want to set the value of an item in a list. The code that does this has to work regardless of the depth to the list. For instance set the value of r[[1,1,1,....,1,1]] to 9. Lets say the list called ...
0
votes
0answers
16 views

How to embed NIntegrate inside NDSolve to solve complex functions? [on hold]

I try to solve complex nonlinear PDE functions with intergrations using NDSolve in Mathematica, but failed. To simplify my problems, I wrote the following codes, but it does not work. ...
1
vote
1answer
19 views

Optimize a parametric matrix to get a lowest possible eigenvalue

This question is a followup of Plot the lowest eigenvalues of a parametric matrix Now I can get the lowest eigenvalue LowEign(t) of the matrix for a given t numerically. When I plot the LowEign ...
0
votes
2answers
32 views

Unable to plot function with exponentials or to find all roots

I am not able to Plot[(-1)^x + 2^x - 2 x - 1, {x, -4, 4}] directly. Some rework might be needed with complex branch cuts perhaps. There are real roots at $ x=3, ...
1
vote
2answers
26 views

Automatic process to replace missing values, coming from a second matrix

I have a large starting matrix with missing values in different columns. I want to replace this missing data as follow. First I have to check the group (last column in starting matrix) and go to a ...
3
votes
0answers
22 views

How to remap graph properties?

Graph objects support both custom properties, which do not have special meanings, and standard properties, which may be used by some functions. When importing from ...
0
votes
0answers
17 views

Evaluating the cumulative multivariate hypergeometric distribution

Suppose there are 5 black, 10 white, and 15 red marbles in an urn for a total of $N=5+10+15$ marbles. You randomly draw $n=6$ marbles without replacement. The probability that you pick exactly two of ...
4
votes
0answers
32 views

Empty WhenEvent action crashes kernel

Bug introduced in 9.0 and persisting through 10.4.1 WhenEvent is new in 9.0. This is an example from the docs, slightly modified (action is wrapped in ...
0
votes
0answers
43 views

Bad behavior of Manipulate with a Greek variable inside

I'm getting bad behavior from Manipulate in Mathematica 10.4.1. A very basic demonstration: ...
2
votes
0answers
42 views

FrobeniusSolve: how does it work?

Can someone suggest any reference to read? I would like to understand how the algorithm works.
6
votes
1answer
57 views

Understanding evaluation and typesetting

Background So, one could be surprised by the fact that: Hold @ Grid[{{1, 2}}] (*or*) Hold @ Graphics @ Disk[] This issue and methods of prevention are ...
0
votes
0answers
28 views

How to use NDSolve for mixed types of several equations?

I have three equations, one is partial differential equation and another two are not. They are just normal algebra equations but coupled with the differential equation. I wanna use NDSolve to get ...
1
vote
2answers
40 views

Discard Elements of list with given criteria

I have the following list: ...
5
votes
1answer
68 views

Why I cannot change the AxesStyle of the Plot?

Bug introduced in 8 or earlier and persists through 10.4.1 I am trying to plot the following single variable function: $$\small\frac{180 \sqrt{\pi ^2-625 t} \left(\pi ^2 (36 t-25)-1500 t \left(45 ...
0
votes
0answers
30 views

Handling Inequality with condition

I have verifying inequality using Mathematica using Simplify command For Example I want to check whether inequality a<f ...
0
votes
0answers
26 views

Integral t^2/(1+t^4) using residues theorem [on hold]

I am trying to figure out how to find the integral of t^2/(1+t^4) dt with residue's theorem.
1
vote
2answers
31 views

MathLink library and undefined references

I am trying to use C++ programs through MathLink in my notebooks, but I cannot compile successfully the simple programs included in Mathematica. I do not have a specific question, I am just looking ...
4
votes
3answers
140 views

Using different style on segments of a plot [duplicate]

Is it possible to plot a function with two different colors? To illustrate, let's have: Plot[Sin[x], {x, 0, 2 π}] which plots a curve. And I would like it to be ...
5
votes
3answers
257 views

How to convert a string into a structured list

I am trying to use an efficient notation for the timing of sounds that i can play in Mathematica. I would like to parse the string "{ab{c{de}}f}" as the list ...
1
vote
0answers
21 views

Where do DistributeDefinitions and ParallelNeeds put their definitions for newly-launched kernels to find

I'm sorry to keep banging on the definition distribution bell, but here is another (hopefully well-focused enough) question on that vein. If one is trying to distribute the definitions in a package ...
2
votes
1answer
43 views

Plot the lowest eigenvalues of a parametric matrix

The question here is somewhat related to the comments in Computing eigenvectors and eigenvalues I have a matrix M, say 400 by 400, and all elements depend explicitly on one parameter t in a ...
1
vote
2answers
53 views

Count pairs from a List

I have a list of numbers: ...
1
vote
0answers
36 views

Plotting huge amount of data with non-default colour function

I want to plot a huge amount of binary data (a 2700x2001 matrix, 5402700 points), and for that I am using the Graphics[Raster[]] function. With just that command, ...
2
votes
0answers
64 views

How to fit two datasets with common fit parameters?

I have two data sets which go: ...
2
votes
1answer
29 views

Basic computations in frequncy domain

I have been trying to find documentation on performing basic operation with transfer function models but have been unable to do so. By basic operation I mean, e.g. Multiply controller transfer ...
2
votes
0answers
75 views

Mathematica Newmark Optimization

Here is my Mathematica code which implements the Newmark method to solve a equation of motion. The variable "ag" contains the accelerations from an earthquake record. Is it possible to optimize this ...
0
votes
0answers
31 views

Manipulate axis scale on a ListPlot

Use this code to generate my problem ...
0
votes
3answers
72 views
0
votes
0answers
28 views

Mathematica showing wrong plot for function f(x) = 3/2 +( Sech[1/x]/x)^2? [on hold]

I tried plotting this function for a homework assignment and got some weird result, and putting the same function in to WolframAlpha gave me the correct answer. The function I'm trying to plot is ...
0
votes
1answer
34 views

Independent test of residuals, absolute member equal zero

Does Mathematica offer any test for confirm independence of residuals? except DurbinWatsonD. And I would like to ask how to make some test in regress function which tests absolute member equal zero. I ...
1
vote
1answer
84 views

Is there a package to find ALL exact roots of a polynomial, if they exist?

There are polynomials with roots not expressible with radicals but expressible as trigonometric or other functions, for which Solve[] only returns ...
0
votes
3answers
67 views

How do I create a circulant matrix? [on hold]

How do I create an $n \times n$ circulant matrix? I couldn't make ToeplitzMatrix do it for me.
1
vote
1answer
65 views

Syntax f[x_][y_]

Need to understand the principe of the distinction between f[x_,y_] and f[x_][y_] It seems also that ...
4
votes
0answers
44 views

Dealing with a nonlinear PDE using FEM

As far as I can see in the Mathematica documentation center, there are no built-in ways for solving nonlinear PDEs using Finite Element Method (FEM). I am dealing with a simple nonlinear ...
2
votes
2answers
132 views

How can I get LogIntegral[z] to be printed as “li[z]”?

I have no problem with the current formatting of the function, but for the sake of the reader less familiar with Mathematica functions, is there a way to define, say, ...
0
votes
1answer
33 views

Why do I not get a result when there is no error message? [on hold]

I've typed in the following equation: Solve[((h*s + l - r*s - r)/(s^2 + s)) (1 + s) - h == (h*s + l - r*s - r)/(s^2 + s) - r, r] and it produces: ...
1
vote
1answer
21 views

Passive Transformation does not return the expectedt result due to precision of expressions

So I wish to perform a passive rotation in N dimensional space. Let me take N=5 for this question. ...
1
vote
0answers
60 views

Computation of a Fresnel Diffraction pattern with Discrete Hankel Transform

In the next link: Computation of Hankel Transform using FFT (Fourier) Rainer implemented a great solution given in the next reference: Manuel Guizar-Sicairos and Julio C. Gutiérrez-Vega, "Computation ...
2
votes
2answers
78 views

How to copy Coordinates of “Get Coordinates” in Figure?

I am trying to reproduce the answer here about Recovering data points from an image. I click the figure and press "Get Coordinates". I would like to copy the four coordinates by CTRL-C and then paste ...
0
votes
0answers
15 views

Théorie de Fourier in Sontag`s book [migrated]

I was reading Sontag`s In America and she mentions: "La théorie de Fourier sur les douze passions radicales.." What is this theorem about?
0
votes
0answers
15 views

ParallelDo does not work, when using variables from other parts of the script

I have a script doing a large amount of calculations with very big matrices that takes so long; so, I want to parallelize pieces of the script to be executed on multiple kernels. For instance, the ...
6
votes
0answers
52 views

benchmark of Mathematica's FEM?

Does anyone have any numbers on how mathematica compares to other commercial (eg ANSYS) or free FEM softwares (eg. FreeFEM++, FEniCS, elmer)? If this is too vague say solving the diffusion equation in ...

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