All Questions

I am trying to define a function for future NDSolve use oweqn = (1/(c)^2) D[y[t, x], {t, 2}] - D[y[t, x], {x, 2}] + k1 y[t, x] = 0 Where I predefined $c$ to be a ...

I am new to Mathematica, now I have an expression Implicit\[Omega]Zero with some parameters $\lambda1,\mu rr,\theta s,b0,a,b1,\omega$ Now I want to find the $\omega(...

Is there a way to control the vertical spacing between input and output cells? If CellMargins is supposed to do it, then what am I doing wrong? In[8]:= CellMargins -> {{1, 1}, {1, 1}}; a = 7 Out[9]...

Why is PolynomialQ[y^2,x] True? The documentation says PolynomialQ[] returns ...

Find the $z$ such that $|z + a| \leq |z| + |a|\cos(\arg(z))$. My approach is to use Resolve: ...

I want to tridagonalize a sparse matrix using the Lanczos algorithm. I am working with a very large sparse matrix and I need some speed. In the following for example ...

The UnsignedInteger64 data format should be able to encode correctly any integer in $[0,2^{64}-1]$. When using this data format with ...

Version: all 12.x OS: Windows 10 and MacOS I am having an issue with Export not clearing memory after it is done with exporting to an .mx file. I have reviewed other posts concering memory issues with ...

Problem : Let x,y,z be non-negative real number whose sum is 1. Find maximum of 0.2x + 0.2y + x^2*z + y*z^2 What I did first was reducing variable. ...

I have the following input: ...

I have a set of data as: data = {{0, 0.046}, {40, 0.111}, {80, 0.291}, {120, 0.808}, {160, 1.742}, {200, 3.319}, {240, 5.017}, {280, 5.503}, {320, 5.897}} With ...

I'd like to use NetNestOperator on a NetGraph that has custom input / output port names, such as ...

If I copy something into the clipboard then use var=Paste[]; I get Null in the var and the ...

I have a list called matcoeffE which has dimensions {10, 9, 7, 2}. However, I want to build a matrix with dimensions ...

I am trying to model a 2d heat transfer in fluid flow with nonlinear heat capacity Cp (e.g. Cp=1 + T[t,x,y]). This benchmark problem is described as: the left side of the plate is heated, and the ...

I am trying to compute fractional function in mathematica using: https://resources.wolframcloud.com/FunctionRepository/resources/FractionalD for example: ...

I am trying to show that a given inequality is true for some triple but I am having trouble finding anything. Here is a tiny version of what I am working with: We define the following polynomials <...

Let me first show what I'm trying to do, and then I will ask the question. I defined three function ...

I have a time-dependent function a[t], which comes from solving various differential equations. Therefore, to obtain the different values of ...

I want to define the velocity vector by the following relation and evaluate the norm of the vector by using the Minkowski metric. I have defined the tensor x (position tensor) in xAct, but I don't ...

I am trying to integrate a function $$\int_R \frac{1}{(\sinh|T-t_1+t_2|)^{\frac2m} (\sinh|t_1-t_2|)^{\frac2m}} \left(\frac{\sinh|t_2|}{\sinh|t_1|}\right)^{\frac1m} \left(\frac{\sinh|T-2t_1+t_2|}{\sinh|...

I would like to attempt to calculate the laplacian operator using index notation and shoow that it gives the usually expected laplacian in spherical coordinates. I am able to do most of the steps ...

Here is the plot I want to do: ContourPlot[3 Abs[x] y (y^2/x^2 - 1/3) - 2/(Abs[x] y) == 3 Sqrt[1 - y^2/x^2], {x, -20, 20}, {y/x, 1/Sqrt[3], 1}] However when I ...

I have a function f[x] with a high-dimensional vector input and a scalar output. I am looking to minimize this function while constraining some of the components of ...

Given a linear time-invariant system: $$x'(t)=Ax(t)+Bu(t)$$ with initial state $x(0)=x0$ and final state $x(T)=xT$. The performance measure to be minimized is: $$∫_0^Tu(t)^2dt$$ The most important ...

I have code to plot the zero contour of a function. This function is symmetric about the x=0 axis, but I only want to display it in the first quadrant. Additionally, I currently set up the axes as a ...

I have generated eigenvalues of '1' 1000x1000 matrix of CircularOrthogonalEnsemble and saved it in a csv file using Export. Now ...

Is there a way to either make FindMinimum do an exact computation or Minimize find also the local minima? Or other ideas to find ...

Consider some sound: ViolinNote = Sound[SoundNote["G", 1, "Violin"]] We may plot the periodogram: ...

I'm fairly new to Mathematica programming. I'm writing a small program that needs to handle text file streams to write output to and read input from them. Although I'm closing the file streams at the ...

I have a list of lists: ...

I've been tempted to use Mathematica to create some artistic musical animations. That is, if I have a music file, I want to be able to edit, for example, its waveform animation. For example, get ...

It seems that Hebrew fonts in general are not visible in the Notebooks, for v. 12.3. Sometimes they overwrite neighboring English text. I have checked the fonts, text color, etc. -- nada. If I export ...

The idea is that I’d like to try to use Mathematica to work through proofs. So if a proof says, “Let there be a vector space V…”, I would like to see a concrete representation of that vector space in ...

I have seen the documentation for Translate (https://reference.wolfram.com/language/ref/Translate.html), which allows one to translate a graphics primitive (like <...

I am trying to do the following: Create a list as Table[Subscript[\[Beta], i] _, {i, 1, dim}] And then use this list to define a function: ...

There is a similar post: How to specify the domain of a variable?, but it doesn't work well for me. I want to evaluate the integral below, with a parameter $\gamma$. The result is obviously different ...

I'm trying some multidimensional Chebyshev fits. First, define a wrapper to prevent premature symbolic evaluation (I don't want a power series result): ...

Been doing a school project, where I am asked to simulate a roulette wheel with 18 Red tiles, 18 Black tiles and 2 Green tiles. The individual in the scenario bets $n on 'Red'. If the wheel lands on ...

Can you help solve this: ...

Is it possible to plot an asymptotic bode plot. I am interested in verifying my straight line bode plot approximations done by hand by using mathematica but the bodeplot function generates the curved ...

I am working on an HJB recently and wish to get a numerical result. Can NDSolve on Mathematica 12.2 handle this? $$ V_t+(e^{-\sqrt{t}}+0.4e^{-2.5t}+0.01x)V_{x}+1.12e^{-2t}V_{xx}=\frac{1}{2}e^{-3t}\...

Using Wolframalpha or inline free format you can obtain a nice representation of a sum of vectors. An example is shown below. Whish is the hidden code? (or a code that make the same representation). ...

As a trivial example, here are two vectors: f = {{1, 1}, {2, 2}, {3, 3}, {4, 4}} s = {{-1, 2}, {-2, 4}, {-3, 6}, {-4, 8}} It is instantly clear (apart from my ...

I've observed a puzzling behaviour of Coefficient[] for negative exponents and I'm wondering if I was always just relying on undefined behaviour or if there is a ...

As I was helping an OP with a question involving Vietnamese currency, I didn't realize at the time that the currency amount was not being interpreted accurately (or so I think now). Apparently, the ...

I'm trying to plot the following VectorField: VectorPlot[{x/Sqrt[x^2 + y^2], y/Sqrt[x^2 + y^2]}, {x, -5, 5}, {y, -5, 5}] I want to use a VectorScaling-option such ...

1.3 A simple harmonic oscillator consists of a mass m and a spring with stiffness constant k. It moves in one dimension x(t) with velocity v(t) where x(t) = A cos(wt + φ) and v(t) = -x(t) = −wA sin(wt ...

Please tell me What is the right command for needs Vector Analysis in 11.3. The Vector Statements are not working

For positive integer k, for any c>0, does there exist k_0>0 that depends on c, such that: