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3 votes
3 answers
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Create sublists whose totals exceed a certain threshold and that are as short as possible

list = {2, 1, 8, 10, 1, 4, 4, 5, 3, 4, 4, 11, 12}; th = 10; It is easy to create sublists whose totals don't exceed th: ...
eldo's user avatar
  • 77.9k
1 vote
1 answer
32 views

Using a pre-rendered image of a plot within a Mathematica Figure

I want to plot new data over data that I only have in the form of a figure in order to be able to make a comparison. Say for example I have only the image (not the original data) produced by (or ...
Kvothe's user avatar
  • 4,591
0 votes
2 answers
61 views

Numerical and analytical solutions do not agree

Hi everyone could anyone have look why this code is not running? ...
Felipe Dura's user avatar
2 votes
1 answer
52 views

Contour shading: how to shade only the positive contours?

...
KZ-Spectra's user avatar
2 votes
1 answer
46 views

Why there have the difference beween the DirichletCondition and directly given boundary condition

The simulation code (The code) TH = 800; TL = 300; U = 1000; J = 1; [Alpha]p[x_] := 1.483110^-3 - 1.390510^-5 T[x] + 5.396410^-8 (T[x])^2 - 8.808810^-11*(T[x])^3 + 5.061810^-14 (T[x])^4; [Kappa]p[x_]...
liaotianjun's user avatar
3 votes
2 answers
86 views

Solving three equations with two unknowns with constant parameters

I have the following two equations: 'r1andr2. Here,n, x, ...
SciJewel's user avatar
  • 514
3 votes
1 answer
40 views

Entity Creation

I had a city called "Lavaresque" which is not known by the interpreter. The following command Interpreted["City"]["Lavaresque"] failed ...
Franck's user avatar
  • 421
13 votes
1 answer
556 views

How to draw a number of circles inscribed in a square so that the sum of the radii of the circle is greatest?

I have a square with length of side is $a$. How to draw a number of circles inscribed in a square so that the sum of the radii of the circle is greatest? In the below picture is six circles inscribed ...
minhthien_2016's user avatar
0 votes
1 answer
81 views

How to obtain a solution to a system of equations using the method of successive approximations?

It is necessary to obtain an analytical solution to a system of equations using the method of successive approximations for $\alpha$, $\gamma$, $\delta$, where $z\Omega>2$. $ \delta=-\...
user2272592's user avatar
2 votes
2 answers
95 views

How to transform this combination of $ _2F_1 $?

Following my previous question How to transform this MeijerG $G_{3,3}^{2,3}$ into a hypergeometric function $ _2F_1 $, I transformed a MeijerG function $G_{3,3}^{2,3}$ below into a combination of ...
Gallagher's user avatar
  • 795
0 votes
1 answer
34 views

How to transform this MeijerG $G_{3,3}^{2,3}$ into a hypergeometric function $ _2F_1 $

I want to transform the MeijerG function $G_{3,3}^{2,3}$ below into a hypergeometric function $ _2F_1 $: $$G_{3,3}^{2,3}\left(\frac{\kappa -z}{z},\frac{1}{2} | \begin{array}{c} \frac{1-\kappa }{2},2-\...
Gallagher's user avatar
  • 795
1 vote
2 answers
40 views

How can I use the output of NDSolve as the initial condition for a Delay Differential Equation?

I am trying to investigate some properties of DDEs with time-varying delays. As an approximation, I am trying to evaluate a basic DDE from time -10 to 10 with a specified constant delay, and then ...
Kit Fynaardt's user avatar
8 votes
1 answer
145 views

List[...] + Association[...], or Association[...] + List[...], when does the order matter?

Values of a list can be added to an association's values like so, ...
Carl Verdon's user avatar
1 vote
1 answer
55 views

Showing maximum in DensityPlot

I have plotted a function as a density plot and I would like to add a line to show the maximum value for each A (vertical axis). ...
questionerno8's user avatar
0 votes
0 answers
67 views

Lists not equal despite containing the same components

Lists not equal despite elements of each list being equal? $Post=If[ArrayQ[#],MatrixForm[#],#] This just converts anything in Array form to Matrix form. The ...
am567's user avatar
  • 547
0 votes
0 answers
44 views

How to preserve symbols under brackets?

Consider, e.g., a symbol =>. In Mathematica, it gets automatically converted into $\ge$. However, if I put the converted symbol inside the "" brackets (...
John Taylor's user avatar
  • 5,851
5 votes
1 answer
272 views

What algorithm does Mathematica's `FindSequenceFunction` use, and can it be replicated in Python?

I am curious about the algorithm used by Mathematica's FindSequenceFunction to identify patterns in sequences. This function is powerful in finding closed-form ...
user avatar
0 votes
1 answer
47 views

Any other 3d plot marker except sphere for ListLinePlot3D?

Here is one sample Mathematica code: ...
codebpr's user avatar
  • 2,423
4 votes
3 answers
384 views

Why is DSolve unable to solve this first order homogeneous ode with IC?

This is first order homogeneous ode from undergraduate textbook, which can be solved using standard $y=u x$ change of variables. But DSolve can't. Could someone figure out why? I show below that ...
Nasser's user avatar
  • 146k
0 votes
2 answers
51 views

How to find the nearest point using RegionNearest for this case?

Consider the following region: ...
John Taylor's user avatar
  • 5,851
5 votes
1 answer
291 views

GeoJSON Problems - UK Parliamentary Constituencies

I want to plot the new parliamentary boundaries for the upcoming general election. This will use an NIHR API to grab the map location of the FID=3, the 3rd parliamentary constituency in alphabetical ...
Tomi's user avatar
  • 4,548
1 vote
0 answers
50 views

Straightening out rumpled striped bedsheets

I was motivated to investigate this from an seeing a Greg's Hurst answer for a different question. I was curious how to find out what the sheet would look like when flattened with proper size and all ...
Teg Louis's user avatar
2 votes
0 answers
65 views

NDSolve: why is the solution error reaching a limit larger than machine precision?

Let us take the following differential equation example: $$ \dot u^2=\mu^2(1-u^2)(1-m u^2),\quad u(0)=0. $$ According to Wikipedia, the analytical solution can be established with Jacobi elliptic ...
Meclassic's user avatar
  • 1,035
3 votes
4 answers
362 views

Simplification of nonessential "I"

I am banging my head trying to simplify following expression to get rid of the nonessential "I" (I know, I can do it by hand, but this is only a toy example): ...
Daniel Huber's user avatar
  • 53.1k
0 votes
0 answers
41 views

Compressed image using SVD draws a clear line between blank part and part with a drawing. Why? [closed]

I'm trying to compress grayscale images using SVD. This is the original image: Yes, there's a lot of blank space. I then choose the x% largest singular values, perform the transformed matrices ...
Elizabeth Middleford's user avatar
0 votes
0 answers
27 views

NBodySimulation with pair-wise force a function of acceleration?

How does one construct an NBodySimulation in which the custom PairwiseForce law involves acceleration? I'm attempting to ...
James Bowery's user avatar
-4 votes
2 answers
107 views

How can we solve this probability problem through code?

Person A and Person B each have four cards, with each card marked by a number. Person A's cards are marked with the numbers 1, 3, 5, 7, and Person B's cards are marked with the numbers 2, 4, 6, 8. ...
csn899's user avatar
  • 4,351
2 votes
0 answers
30 views

Position Graphics using FigInset in SciDraw

I would like to position Graphics into FigurePanel of SciDraw using real coordinates. It ...
Moonwalk's user avatar
  • 661
0 votes
0 answers
36 views

Suppress preliminary output from wolframscript

$ /opt/homebrew/bin/wolframscript -code "AirTemperatureData[Here,Now] // First" ...
Steven Buehler's user avatar
1 vote
0 answers
59 views

Integration by parts for Green's first identity

How should one implement $$\int _{\Omega }\nabla u\cdot \nabla v\,d\Omega \ =\ \int _{\Gamma }v\,\nabla u\cdot {\hat {\mathbf {n} }}\,d\Gamma -\int _{\Omega }v\,\nabla ^{2}u\,d\Omega\,,$$ Symbolically ...
FreeMind's user avatar
  • 141
0 votes
0 answers
30 views

Problem Derivative (D) of function defined with Piecewise or UnitStep functions - SIMPLE BEAM PROBLEM, 3 SUPPORTS

I am solving a simple structural beam problem using slope-deflection approach - 3 support A(left- fixed), B(middle- pin), C(right - pin). Beam AB - uniform load, Beam BC - concentrated load in ...
SAK's user avatar
  • 63
4 votes
1 answer
124 views

How to write a rule that matches alternatives but return one of them always?

Consider the following rule: $rule={"Period ID"|p:"Period":>p}; This rule will match ...
user13892's user avatar
  • 9,483
3 votes
1 answer
97 views

How to `Collect` where `var` is one expression?

Edit: Clear["Global`*"]; expr1 = (a + c - b + 1)^3 + (-b + a + c + 2)^4 // Expand For test case expr1, this is the ...
138 Aspen's user avatar
  • 1,541
0 votes
0 answers
37 views

Replacement not working as desired [duplicate]

The following replacement works fine ReplaceAll[1/F[x],F[x]->y] (*1/y*) but this doesn't ...
qreus's user avatar
  • 343
0 votes
0 answers
55 views

DSolve solves the PDE in Wolfram Mathematica, but not in Wolfram Cloud

Good evening! I have the following Mathematica code. ...
Kώστας Κούδας's user avatar
1 vote
1 answer
38 views

What is wrong with my neural network runtime?

Having started working with Neural Network in WM 14.0 I encounter the following strange problem. The code ...
Konstantin's user avatar
-4 votes
0 answers
38 views

Square matrices proved by the negative method [closed]

Given A,B square matrix nxn, a^2=b^2 and b does not equal zero. Does a=b always true? How to proof by way of negation?
user3340983's user avatar
4 votes
1 answer
76 views

SetOptions does not work for ContourStyle of ContourPlot3D?

$Version 14.0.0 for Mac OS X ARM (64-bit) (December 13, 2023) This seems to be similar to Global LabelStyle option does not work with SetOptions and SetOptions for ...
Lacia's user avatar
  • 2,433
1 vote
1 answer
110 views

How can I make a data randomly like form of LaTeX

This is a data in LaTeX, I input by my hand. ...
Thuy Nguyen's user avatar
  • 1,109
0 votes
0 answers
53 views

Import as Table imports 51d60 as 5.1*10^61

I have a data for which the first column has data such as 51d60, 52d60 and so on. When I do Import["filename.txt","Table"], the first column imports as 5.1*10^(61) instead. What is ...
user99322's user avatar
0 votes
0 answers
54 views

How to move a Mathematica plot between two notebooks?

I have a long complicated notebook that performs some simulations of a physical system and generates a series of 3D plots. From that original notebook I made a few new ones for modifications to the ...
quantum_loser's user avatar
0 votes
0 answers
49 views

Compare Numerical and analytical solution for a simple case!

I wanted to check this equation for analytical and numerical solution but they don't meet each other?? ...
Felipe Dura's user avatar
6 votes
3 answers
219 views

Composition of vectorvalued functions

Suppose I have two functions $f,g:\mathbb{R}^2 \to \mathbb{R}^2$ and that I want to compute $g(f(x,y))$. As an example, let's take $f(x,y)=(x+y, x-y)$ and $g(x,y)=(y^2,x^2)$. Then, $g(f(1,2))=(1,9)$. ...
user2978125's user avatar
2 votes
2 answers
97 views

Series expansion not working with $\sqrt{1-x^d}$

Why can't Mathematica expand simple functions like $$\sqrt{1-x^d}$$ in series? When I give particular values of $d$, then it simplifies but not otherwise. For now, I want $d \in \mathbb{N}$, and want ...
Sanjana's user avatar
  • 195
2 votes
2 answers
143 views

How to calculate this improper integral?

How to calculate the Integral involving MarcumQ function whose Integral interval is (0, +Infinity)? Any help (code or reference) would be greatly appreciated. ...
138 Aspen's user avatar
  • 1,541
3 votes
2 answers
92 views

Solving a differential equation with a singularity

I am interested in solving the differential equation, $$ y'(x) = -Ae^{-3y} $$ subject to the condition that $y(0) = 0$. This has an analytic solution, $$ y(x) = \frac{1}{3}\ln(1 - 3A x) $$ but I am ...
MarcosMFlores's user avatar
0 votes
0 answers
22 views

Eigen values of a symmetric real valued matrix [closed]

Why does the eigenvalue function not work here? ...
SciJewel's user avatar
  • 514
0 votes
1 answer
37 views

Block matrix of arbitrary dimensions

I have a block matrix that has a general form as sketched below: (excuse my handwriting). The dimension of each individual matrix is indicated. The 0_{ixj} are zero matrices of dimension i x j. My ...
igunnarsson's user avatar
2 votes
1 answer
132 views
+50

Using mathematica to find the equation of curves, by providing images, providing constraints, or both

By "collaborate", I mean to give some instructions or constraints. Consider the following curves: (as examples, only to illustrate my question in a better way): Curve (I): Assume it is f ...
Hussain-Alqatari's user avatar
0 votes
0 answers
42 views

How to manage tensor in mathematica

I open this topic because I would like to ask the community how to handle this tensor sum regarding solid mechanics. I apologize if what comes next will generate some confusion, but I am new to using ...
Emanuele Crespino's user avatar

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