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0 votes
0 answers
7 views

Purple color text related with RowBox

Type the first line of following code and press enter key. ...
  • 3,529
0 votes
0 answers
10 views

How can I modify the code to make the analytical expression of the derivative function in the image in a simplified form after a general division?

...
  • 797
0 votes
0 answers
28 views

Problem with bifurcation diagram for driven damped pendulum

I am using the following equation of motion for a driven damped pendulum: $$\frac{d^2\theta}{dt^2} = -\frac{g}{l}\sin \theta -\gamma \frac{d\theta}{dt} + A\sin(\omega_d t)$$ where $\theta$ is the ...
  • 689
2 votes
0 answers
15 views

Is it possible to prevent the very first evaluation of Dynamic when it appears on screen?

Is it possible to tell DynamicBox to not run its very first dynamic evaluation when it appears on screen, and instead, to just show its ...
  • 19.3k
0 votes
2 answers
48 views

Collect doesn't work correctly

I have this expression ...
1 vote
1 answer
47 views

Difficulty to Solve the Generalized Wave Equation

Given the following problem $$u_{tt}-\frac{v}{2}\cdot u_{xx}+\frac{v}{2}\cdot x^2 \cdot u(x)=0 $$ $$u(x,0)=f(x)$$ $$u_t(x,0)=g(x)=0$$ Where $ f(x)=y_0(x) $ $y_n$ are the Eigenfunctions that defined ...
0 votes
1 answer
33 views

Properly Format Vertical Bar with Supersubscript

I'm having trouble emulating the following (extra long) vertical bar format in a text cell: The closest I could get to in a text cell is: which doesn't look great; it's underlying code is ...
  • 5,221
0 votes
0 answers
24 views

Flat Group Delay of a Transfer Function, Units? [closed]

I'm trying to find a flat Group Delay (tg) of a Transfer Function [H(s)] and having trouble with units. The filter has a given Group Delay (tx) that needs to be balanced with this filter's tg. The ...
2 votes
1 answer
74 views

Apply ReplaceAll to a whole notebook

I'm an avid tauist (tauday.com) and I don't like the fact that Mathematica displays equations with $\pi$ instead of $\tau=2\pi$. I know that I can "force" it to display $\tau$ by e.g. ...
  • 135
1 vote
1 answer
65 views

How to express the argument through the function?

I would like to express argument $d$ through $f$ and $B$ and to get $d(f,B)$ $$f(d,B)=B\left(\left(\frac{1}{4}-\frac{d}{B}\right)\left( 1-\left(1- e^{-30d/B} \right)^8\right)+\frac{2/B}{3+1/B^2}\left(...
  • 781
1 vote
0 answers
23 views

Invalid PeriodicBoundaryCondition for Navier Stokes problem using NDSolveValue

Background: I'm looking to have a 2D re-entrant channel of a geophysical flow that is forced by a wind stress at the surface ("taux"; below) and experiences planetary rotation ("cor&...
  • 11
1 vote
0 answers
47 views

One more incorrect result of FunctionMeromorphic and FunctionAnalytic

Two years ago I submitted a bug in FunctionMeromorphic (That bug still persists in 13.2.). Here is one more incorrect result in it and ...
  • 21k
1 vote
2 answers
47 views

Sorting by power

I want to sort this table by column "d" such that Mathematica should also take the exponential values into account. Can somebody help me here?
  • 11
2 votes
1 answer
67 views

Limit of Taylor coefficients

I want to calculate the following limit: b[n_] := (D[1/(1 - t), {t, n}] /. {t -> 0})/Factorial[n] Limit[b[n], n -> ∞] (* Indeterminate *) where ...
0 votes
0 answers
33 views

Hyperbolic Fourier series in Mathematica?

The hyperbolic Fourier series has nonlinear periodicity, and can be applied for wave modeling. https://arxiv.org/abs/2110.00148 The proof herein is quite laborious to reproduce here, but my question ...
  • 991
1 vote
1 answer
47 views

Function f[a__][b__] with double inputs and definitions/automatic rules

I have a function of the form f[a___][b___] which I would like to apply rules to, for example: ...
  • 717
2 votes
1 answer
29 views

Run Initialization in Manipulate Manually

Although I have received a lot of help, there is a rather difficult question. Let we have a system with parameter: $$x_{n+1}=x_n^p$$ As long p changes, we have to ...
  • 817
0 votes
0 answers
46 views

A question about integrals and numerical integration

I have a function $f(r)=(1+r/2)^{(-5/r)}-1/r$ and I need to solve the integral of its reciprocal. However, I failed. Is there a way to get the analytical formula of this integral? If it is possible to ...
1 vote
1 answer
46 views

Graphing perpendicular vectors to a 3D graph

I am brand new to mathematica, I was wondering how can one obtain a curve similar to this one : Where the vectors are perpendular . Thanks for your help the curve is $f(x,y) = \sin(xy)$ Here is the ...
1 vote
0 answers
21 views

Can Mathematica import uv information from 3d model?

Question1: Does mathematica's supported 3d file format can import uv information such that we can split the model polygons and keep the texture? https://en.wikipedia.org/wiki/UV_mapping Question2: If ...
  • 8,429
7 votes
2 answers
258 views

Dot Product and Simplification

How to simplify the expression a b . x/((a b) . x) Where a is a scalar and b and x are vectors. I have tried the usual Simplify, FullSimplify, TensorExpand etc. ...
  • 775
6 votes
3 answers
248 views

How can I check if the matrix is of the following form?

$\left( \begin{array}{cccccc} -a & 0 & 0 & 0 & 0 & 0 \\ 0 & a & 0 & 0 & 0 & 0 \\ 0 & 0 & -a & 0 & 0 & 0 \\ 0 & 0 & 0 & a &...
  • 3,399
1 vote
1 answer
43 views

Partition with cyclic padding

I am using v12.2.0 on Win7-x64. The difference between case 1 and case 2 is that the list being partitioned has 5 elements vs 4 ...
  • 28.7k
-4 votes
1 answer
56 views

Please show code for mathematica [closed]

. Using Mathematica, solve the following differential equation system by completing the following steps: (𝐷 + 2)π‘₯ + 𝐷(𝐷 + 1)𝑦 = 3𝑒^βˆ’π‘‘ 𝐷π‘₯ + (𝐷 + 1)𝑦 = βˆ’3𝑒^𝑑 a. Use DSolve to solve the ...
  • 1
1 vote
1 answer
58 views

How to convert a Whitaker function to a Coulomb function?

$$ \frac{d^2F}{dx^2}+\left[ 1-\frac{2n}{x}-\frac{l\left( l+1 \right)}{x^2} \right] F=0 $$ The solution of the above equation is the Coulomb function. $$ \frac{d^2w}{dz^2}+\left[ -\frac{1}{4}+\frac{k}{...
  • 319
1 vote
1 answer
45 views

ContourPlot has weird wavy line

I have been using ContourPlot for a complicated but analytic function, which does not need numerical calculations. I am confused to see the result looks like the following picture, where the lines ...
  • 21
0 votes
0 answers
41 views

BoundaryDiscretizeRegion and DiscretizeRegion Commands Generate Meshes with Unwanted "Hula-Skirt" Flashing

Mathematica V13.2 This is a generalized problem. The provided sample involves singularity (1/x or 1/0) candidates, such as Sin[x]/x. Singularities or division by zero equations are the primary focus ...
  • 21
0 votes
1 answer
52 views

Why these two ways of interpolations give different results?

Consider a data file distr.dat. It is a tabulated grid in the form x1,x2, func[x1,x2]. I interpolate it in two different ways: ...
  • 5,112
2 votes
1 answer
42 views

Plot elements of a time dependent matrix

The matrix that I wanna plot the elements are complicated, this matrix is just an example: ...
0 votes
1 answer
47 views

How to compare the numerical with the analytical solution of PDE?

Given the analytical solution ...
0 votes
0 answers
44 views

Controlling my Drone

I have the ambitious plan to paint a wall using a drone. And I would like to do that with Wolfram mathematica. Does anyone have experience flying a drone with their laptop? Is it possible to control ...
0 votes
2 answers
91 views

Why does Minimize return a wrong answer?

I want to find the minimum of the following function, but get a wrong result. What am I doing wrong? ...
3 votes
2 answers
86 views

Computing constrained tuple efficiently

I was wondering what would be the fastest/most efficient way to compute the elements of the set $$\left\{ x\in\mathbb{Z}^{d} \middle| \sum^{d}_{i=1}|x_i| \leq n \right\}$$. I think I could use Reduce,...
  • 147
3 votes
1 answer
96 views

Computing the unitary operator that diagonalizes a matrix

Hello. I am learning in Mathematica how to obtain the unitary operator that allows us to diagonalize the matrix M. Although with U^{-1}.M.U am able to obtain the answer: why doesn't the program ...
  • 133
2 votes
2 answers
72 views

Don't understand an evaluation with BezierFunction

I don't understand the source of the failure of the following attempts to solve an equation involving the following very simple BezierFunction. ...
  • 13k
-1 votes
0 answers
20 views

Travelling Tournament Problem (TTP) IL.P [closed]

"I am attempting to solve the Travelling Tournament Problem (TTP) using the Python library Pulp. However, I encountered a problem with the scheduling constraint, which was not accepted. All the ...
1 vote
0 answers
41 views

Hyperlinks in plain text not preserved when saving in PDF format in Mathematica V13

I have a notebook containing hyperlinks, but when I save it in pdf format (print to PDF) the hyperlinks are not blue and not clickable. According to Hyperlinks not preserved when saving in PDF format ...
  • 121
0 votes
1 answer
45 views

Can someone please explain where I am going wrong in the given argument? Is it obvious that $f(m,s)>0$?

I have a two-variable function $f(m,s)$ for real $m>0$ and $s>0$, and as the first picture shows, it seems that it is always positive; on the other hand, I can easily find the minimum of $f(m,s)$...
  • 161
0 votes
1 answer
50 views

Integrate doesn't give a result for non-linear functions

I use Acegen for Finitie Element formulation that gives out residuals and tangents by taking in the field values as inputs. For this in my residual formulation I need to integrate a nonlinear term ...
  • 1
0 votes
1 answer
80 views

Don't understand the number of levels of "Flatten"

I have a data data={{{-(1/2), -(3/2)}, {1/2, -(1/2)}, {3/2, 1/ 2}}, {{-(3/2), -(5/2)}, {-(1/2), -(3/2)}, {1/2, -(1/2)}, {3/2, 1/ 2}, {5/2, 3/2}}} I want to ...
-1 votes
1 answer
58 views

Closed form of $\int_{0}^{1} \frac{x\log x\log(\frac{1+x}{1-x})}{1-x^2} dx$ [closed]

I need a closed form using Mathematica or otherwise of the integral $$\int_{0}^{1} \frac{x\log x\log(\frac{1+x}{1-x})}{1-x^2} dx $$ This integral converges see here. I am requesting a code with ...
  • 97
-1 votes
1 answer
53 views

Calculate the value of an interval [closed]

I want to calculate the maximum value of the formula given in the code, but it is obvious that my writing is incorrect. How should I modify it? ...
1 vote
2 answers
43 views

Multilinear Function

I have a totally antisymmetric function of n arguments, f[a,b,c,d] = -f[b,a,c,d], which I would like to be multi-linear, e.g. ...
  • 717
0 votes
1 answer
30 views

How to draw a function image within multiple interval definition domains? [duplicate]

Plot[x^3, {x, -1, 3 || 7, 10}] Note that the intervals of the function are separated. There are two intervals, (- 1,3) and (7,10)
  • 797
-1 votes
1 answer
50 views

How to graph the gradient of the function Sin(x,y)? [closed]

I tried graphing the gradient of the following function but i can't manage to do it, anyone can help me please
0 votes
1 answer
60 views

Recording results of Manipulate

I'm studying the effects of some parameter on a complex system. When we change the parameter, the system is converted and we need to write each new state to the list. Problems encountered in using <...
  • 817
0 votes
0 answers
21 views

NDSolve:step size is effectively zero; singularity or stiff system suspected [closed]

...
  • 1
3 votes
1 answer
238 views

Prediction Algorithm [closed]

Trying to identify what algorythm I need to use to predict a battery full time (100%), based on historic data (charge rate is variable). I suspect it's some form of linear regression of a sort, ...
0 votes
1 answer
32 views

How to find the value range of a function with multiple intervals in the definition domain?

FunctionRange[(2 Sqrt[3] (k^2 + 1))/( 3 k^2 - 1), {k, k > 1/Sqrt[3], k < -1/Sqrt[3]}, y] The above function argument has two interval ranges k > 1/Sqrt[...
  • 797
0 votes
1 answer
50 views

The problem with complex numbers

I have one of the roots of the characteristic equation ...

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