All Questions

I have some problems in solving this equation numerically in mathematica. Mathematica give me the error message "NSolve::nsmet: This system cannot be solved with the methods available to NSolve&...

I have a list of solutions from Solve[] in the form ...

Is it possible to search and compare for the price of a certain product e.g "Dầu thực vật Tường An" in different appointed websites, e.g. https://www.sendo.vn, https://www.lazada.vn, https:/...

Below is code for mapping the connectivity of US counties. It comes from the Mathematica reference on "Connectivity of US Counties". I've highlighted 3 shortest paths shown in red. However, ...

I am new with Geometrie and mathematic problems so maybe I said some wrong things. I have an N-dimensional space where there are a set of points (2^N points) where each point has a coordinate like ...

The function is g[x_] := (1/Sqrt[2*Pi])*E^((-x^2)/2) and I'm trying to find an $n$ for Series[g[x], {x, 0, n}], n], that matches ...

Context I would like to compute the MorphologicalEulerNumber of 3D GaussianRandomField as a function of height above a given threshold. Attempt I proceed as follows:...

The following code works just fine with a few caveats. ...

I have a folder of about a million JSON files and I wrote this to convert them quickly to CSV, but the formatting is not correct for the software I'm feeding them into. Here's the code I'm using: <...

I' m working on an audio generator for physics lab, using an Android device and Bluetooth . However, the response of the Bluetooth speaker is wrong. When programmed to deliver, say 3150 Hz, it may ...

One can Import multiple sheets from an Excel file, say sheet "n" with Import["file.xls"][[n]], but how to do ...

I'm new to mathematica so don't have alot of experience with it. I'm currently trying to make code to find the eigenvalues of this matrix but keep getting an incorrect answer - could someone let me ...

I have the following plot: ...

Is there any way to do a problem like this with MMa? I have an infinte set of coupled equations. j is a real integer index where $-\infty<j<\infty$. {a,b,c,d,f} are variables, and K's are ...

Well, my question is the following: I have a .txt file that consists of the following data (this file is much larger than presented here): ...

I have this limit but Mathematica can't solve it??!! ...

I want to implement computation of Macdonald polynomials in mathematica. A similar question was raised in another question 5 years ago (Macdonald-Koornwinder polynomials?), but received no clear ...

When we have a function like $f(x) = x^2-1$ and we expand it in a power series about some $x = x_0$, does Mathematica automatically assume that $x$ is real valued?

list = {1, E, (3/2)*E^2 + (3/8), (5/2) E^3 + (25/8)}; AppendTo[list, 2*E*list[[{x - 1}]] + (2*x - 3) (2*x - 4) (2*x - 5) (1/4)*list[[{x - 2}]]] Let x from 5 to 10, ...

Mathematica 12 is now supporting MDS. DimensionReduce[{{1, 2, 3}, {2, 3, 5}, {3, 5, 8}, {4, 5, 8.5}}, Method ->"MultidimensionalScaling"] The process is straight forward, but there is no ...

I was trying to create a named function using a short syntax (I mean avoid writing Function[]). I thought SetDelayed was the short for Function[], but then I had some issues and realized that maybe #x ...

Can anybody tell me what I did wrong that I don't get a function in my plot? It's empty, there is no line. f[x_] := Cos (x)/(2 - x^2) Plot[f[x], {x, 0, 2}]

I'm trying to solve DSolve[f[x]*(x^2*g''[x] - 2*g[x] + 2) + x*(x*g'[x] - 2*g[x])*f'[x] == 0, g[x], x] for $g(x)$, however Mathematica cannot find a solution. ...

I want to create a random graph with SpatialDegreeDistribution and want the edges to be directed. ...

I have the following differential equation: $ \tag{1} \Delta^{-s}\frac{d}{dr}(\Delta^{s+1} \frac{d R(r)}{dr}) + (\frac{K^2 - 2 i s (r - M)K}{\Delta} + 4is \omega r - \lambda)R(r) = 0$ where $\Delta \...

Let be given a pyramid SABCD. Put H is projection of A on ...

I have a lot of functions (mostly exponential included and more precisely complicated combinations of Gaussian and Slater ones) which decay and become zero in the different points depending on the ...

I’m using Manipulate[] to adjust several parameters, which will eventually generate some figures. After I get the desired view, I’d like to store the set of control parameters so that I can reuse them ...

A ZeroMQ.NET demo could be found at the github ZeroMQ/OMQ_Server, ...

What is the "Q" in built-in symbols such as FreeQ[expr, form], MemberQ[list, form]? (Query?) Thanks.

I noticed that Mathematica 12.3 (also 12.1) kills the kernel when I try to Export a large list to a CSV file. No error messages, no warning, just a hard stop. Here is the code I wrote to replicate the ...

Black returns in Mathematica, a normal black color. With Lighter[] we can make it somehow grey. My question is: How can one make, let's say black, arbitrarily lighter? That is, for example, 10% ...

I have a hard time running this: ...

I was trying to compute the median of a pdf using NSolve, defined such that $$ \int_{0}^{\rm median}p(x)dx = \frac{1}{2} $$ but NSolve seems unhappy about solving for an upper limit of an integral. A ...

I wrote this code below ...

Mathematica does not recognize this special case of Gaussian integral. Integrate[exp(-Q^2-(v^2R^2/16/a^2/Q^2)), {Q, R/(4at)^(1/2), Infinity}, Assumptions -> a >= 0 && t >= 0 &&...

I want to let Simplify know the exact value of a symbol, to resolve logical statements, but don't want it to actually replace it. For instance, I would like ...

how we can obtain a 2D projection of 3D plot. I would to have a plot like this : PS: the plot is a publication paper.

(Title needs improving) I'm trying to find the analytical expression for the attenuation of an AC voltage through a passive low-pass filter. The solution involves finding the time-dependent charge (<...

I want to compare how two vector fields $\vec V_1=-y\hat i+x \hat j$ and $\vec V_1=2\vec V_1=2(-y\hat i+x \hat j)$ various concentric circles $x^2+y^2=a^2$ with $a^2=1,2,3$ etc. I can plot them ...

I'm trying to find a numerical instance (I don't need arbitrarily high precision) of solution to 7 relatively complicated inequalities (plus the region specification) involving 8 variables. The ...

I think I'm experiencing a bug, but perhaps there is a simple explanation and fix. I have many initialization cells in my notebook (a few hundred). As of quite recently, they stopped all evaluating ...

I'm trying to rotate a scalar valued function $$f(\theta,\phi)$$ on a sphere. Following this post, I get $$ \begin{pmatrix} f'(\theta',\phi')\sin\theta'\cos\phi'\\ f'(\theta',\phi')\sin\theta'\sin\phi'...

Imagine I have the following list {{0, {2,3}}, {-1, {5,3}}, {2, {2,6}}, {5, {5,0}}, {0, {1,1}}, {-2, {10,2}}, {3, {4,2}}}; I want to pick the element in the list ...

I have the following code: ...

We should go on with Euler's determining equations for algebraic degree 5. Has anyone some experience with this?

It happens to me a lot when I write a loop, I have to Clear all functions, variables, definitions and etc to be sure my calculations is done correctly. namely as a ...

Could anyone help me solve set of pdes with embedded integration? The pdes below is solvable , but can not be solved when I tried different parameters such as ...

I am having a problem with the "Cases" command. If I execute the following code ...

I want to solve this no-linear differential equation system: $1.2 (1 + 20(r(t)^2 + 2^2 + 4 r(t) \sin(\phi(t)))^2) \ddot\phi(t) + \dot \phi(t) + \phi(t) = 50 \sin(4 t)$ $\textbf{If}$ ($|-r(t)\dot\...