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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 ...
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 ...
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 ...
16 views

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 ...
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 ...
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: ...
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 ...
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 : ...
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 ...
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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. ...
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 ...
32 views

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Syntax f[x_][y_]

Need to understand the principe of the distinction between f[x_,y_] and f[x_][y_] It seems also that ...
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 ...
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, ...
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: ...
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. ...
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 ...
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 ...
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Théorie de Fourier in Sontags book [migrated]

I was reading Sontags In America and she mentions: "La théorie de Fourier sur les douze passions radicales.." What is this theorem about?