All Questions
88,817
questions
0
votes
1
answer
4
views
ReplaceAll for expressions involving negative power
I have an expression:
$exp=1+\frac{1}{x}+\frac{2}{x^{2}}-\frac{3}{x^{3}}$
I am trying to make the following replacement:
$\frac{1}{x^{i}}\rightarrow f(i)$, where f is any arbitrary function.
The ...
0
votes
0
answers
12
views
Transform a continued fraction to an ordinary fraction
I need to calculate (tranform to a 1-level fraction) the following continued fraction:
...
- 1
0
votes
1
answer
21
views
How to plot the region with LineElement when the element number increases?
I want to plot the square wave region for FEM solver, and when the tooth number of the square region is 3, then the total coordinates is 12, when the tooth number of the square region is ...
- 67
2
votes
1
answer
12
views
Alternative Material Models for Finite Element
The Solid Mechanics capabilities of Mathematica make it an interesting alternative to using other software especially when considering multi-physics problems. I would like to collect here (for the ...
- 3,713
0
votes
4
answers
39
views
A puzzle about solving equations
my wolfram version: 13.1
As you can see when I solve this equation directly, I can't solve it
Solve[(A \[Pi]^(3/2))/(2 Sqrt[2] a^(3/2)) == 1, A]
And when I tweak ...
- 1,192
0
votes
0
answers
23
views
Is there any documentation for vibration and solid mechanics research via Mathematica?
I am interested in the solid mechanics (elastic mechanics and structural mechanics, etc.), and vibration, is there any material or documentation in this aspect via FEM in Mathematica?
- 67
0
votes
0
answers
29
views
Improve performance of DeleteDuplicates for list of matrices
I have a matrix $A_0[x,y,z]$ and a list of matrices $B$ with about 30 matrices. Matrix $A_0$ is a function of some parameters $x,y,z$. I create a new list of matrices, say $A_1$ produced by ...
- 539
0
votes
0
answers
10
views
Does .NET/Link work with .NET 7.0 assemblies?
Is it possible to call methods in a .NET 7.0 assembly from Mathematica? If so, then how is that accomplished?
This is my first foray using .NET/Link. I was able to get a test project working that ...
- 271
1
vote
0
answers
19
views
Extract Latent Space Learnt from Neural Network
I would like to visualize and cluster vectors learnt in the latent space of a NeuralNetwork.
I am trying to clusterize audio tokens, but I don't know what they represent. So the task is to ...
- 445
0
votes
0
answers
36
views
Solving a system with Exponential equations [closed]
Given the following system
\begin{align*}
2\cdot 3^x-3 \cdot 2^y&=-22\\
5\cdot 3^x+\frac{1}{2}\cdot2^y&=9
\end{align*}
TThen let $w=3^x$ and $u=2^y$
\begin{aligned}
2\cdot w-3 \cdot ...
1
vote
1
answer
58
views
Vertical GrayScale Plot
I'm trying to make a grayscale plot like the one shown below, except I'd like it to plot vertically.
ArrayPlot seems to only plot horizontally. Is there a way to make it plot vertically or is there ...
- 5,233
0
votes
0
answers
21
views
How do you save and load a Mathematica object (DataDistribution)? [duplicate]
How do I export and successfully reimport a DataDistribution (or other Mathematica object)?
I'm working with an analysis script to run in a cron job regularly.
Building the distribution takes some ...
-1
votes
0
answers
30
views
How can I use matlab or latex plot the core for cooperative game? [closed]
Consider a game of a function v which has floowing ways
$V(1)\geq 12$
$V(2)\geq 7$
$V(3)\geq 10$
$V(1,2)\geq 128$
$V(1,3)\geq 185$
$V(2,3)\geq 18$
$V(1,2,3)=300$
How can I plot such a function in ...
- 1
0
votes
0
answers
22
views
Until Requires Evaluation for each Iteration [closed]
I am trying to better understand Until in Mathematica. To do that, I'm going through the examples in the Mathematica documentation (shown below).
My expectation was that I would hit evaluate once, and ...
- 31
1
vote
1
answer
79
views
Expression substitution
I konw:
$$
a_0=\frac{4 \pi \epsilon_0 \hbar^2}{m_e e^2}
$$
and
$$
\alpha = \frac{m_{\mathrm{e}}^2 e^4}{18 \pi^3 \epsilon_0^2 \hbar^4}
$$
So we can use $a_0$ for $\alpha$,like this:
$$
\alpha=\frac{m_{\...
- 1,192
1
vote
0
answers
39
views
2
votes
1
answer
15
views
Is there a way to extract the function used in NetEncoder[{"Function", ... }]?
Is there a way to — programmatically and with documented functions — extract the function used in a NetEncoder[{"Function",...}] type encoder? I want to ...
- 223
2
votes
1
answer
32
views
Absolute value of $1$ in PlotLegends in ComplexPlot
When using PlotLegends -> "Automatic" in ComplexPlot, it seems that Mathematica always picks some value different ...
- 155
1
vote
0
answers
23
views
Nonphysical results with NDSolve for two coupled nonlinear ODEs
I have a thermal problem, where I have two long strips of metal connected to each other by a dielectric along their length(sketch attached). The lower strip has its temperature defined at each end. ...
- 21
2
votes
1
answer
47
views
0
votes
1
answer
28
views
Lyapunov exponent of Van der Pol-duffing oscillator by varying parametric forcing
For a parametric Van der Pol oscillator as given
x'[t] == y[t], y'[t] == -0.1*y[t]*(1 + f*Cos[1.0*t])*((x[t])^2 - 1) - 0.41*(x[t])^3 + (0.5^2)*x[t]
for ...
- 11
0
votes
2
answers
58
views
Generate n tables of values for functions
After searching for a long time, I can't find how to do what I need with some bold header style.
I need to generate n tables of values for linear functions (f(x)=mx+n), where x varies from -6 to 6, ...
- 1
1
vote
3
answers
78
views
Expressing vectors as linear combinations of a set of other vectors
I have a list of twenty different 125-component vectors.
I have a bunch of other 125-component vectors which are known a priori to be expressible as a linear combination of these twenty.
I want a way ...
- 11
0
votes
1
answer
35
views
0
votes
0
answers
25
views
How to export matrices in `MatrixForm` into png files (in a for loop) [closed]
I would like to export the png file of the output of Table in MatrixForm. The code is in the ...
- 285
0
votes
1
answer
39
views
How to plot the derivative after indicating the value?
I have used the FEM tool to solve this PDE system with control equation and boundary conditions, after calculation the ufun1[x, y] are calculated, and I want the ...
- 67
1
vote
0
answers
64
views
Wolfram Quantum Framework Shows Mixed States as Kets
Wolfram Quantum Framework consistently shows the state["Formula"] for mixed states, defined via some density matrix, in terms of simply kets! Is it ...
- 203
3
votes
1
answer
83
views
Purple color text related with RowBox
Type the first line of following code and press enter key.
...
- 3,561
0
votes
0
answers
25
views
0
votes
0
answers
55
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)$$
where $\theta$ is the ...
- 599
3
votes
0
answers
28
views
Is it possible to prevent the very first evaluation of Dynamic when it appears on screen?
Is it possible to tell DynamicBox to not run its very first dynamic evaluation when it appears on screen, and instead, to just show its ...
- 19.3k
0
votes
2
answers
72
views
3
votes
1
answer
189
views
Difficulty to Solve the Generalized Wave Equation
Given the following problem
$$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$$
Where $ f(x)=y_0(x) $
$y_n$ are the Eigenfunctions that defined ...
0
votes
1
answer
37
views
Properly Format Vertical Bar with Supersubscript
I'm having trouble emulating the following (extra long) vertical bar format in a text cell:
The closest I could get to in a text cell is:
which doesn't look great; it's underlying code is
...
- 5,233
0
votes
0
answers
30
views
Flat Group Delay of a Transfer Function, Units? [closed]
I'm trying to find a flat Group Delay (tg) of a Transfer Function [H(s)] and having trouble with units. The filter has a given Group Delay (tx) that needs to be balanced with this filter's tg. The ...
2
votes
1
answer
96
views
Apply ReplaceAll to a whole notebook
I'm an avid tauist (tauday.com) and I don't like the fact that Mathematica displays equations with $\pi$ instead of $\tau=2\pi$. I know that I can "force" it to display $\tau$ by e.g.
...
- 155
1
vote
1
answer
68
views
How to express the argument through the function?
I would like to express argument $d$ through $f$ and $B$ and to get $d(f,B)$
$$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
3
votes
1
answer
41
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&...
- 31
1
vote
0
answers
50
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
1
answer
65
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
77
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 ...
- 23
0
votes
0
answers
39
views
Hyperbolic Fourier series in Mathematica? [closed]
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
52
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
32
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
51
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 ...
- 61
1
vote
1
answer
48
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 ...
- 11
1
vote
0
answers
23
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
8
votes
2
answers
297
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. ...
- 785
6
votes
3
answers
384
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
45
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