All Questions

1
vote
2answers
39 views

Locate all row and column pairs containing a value in a table

I would like to find all row and column pairs that contain 1 in a table. For example, the row and column pairs that contain 1 in the table are (a,b),(b,a),(b,c),(c,b),(c,d),(d,c),(d,e),and (e,d). <...
5
votes
1answer
55 views

How can I extract docs data from a WRI Workbench template?

I would like to move my docs out of Workbench in something simpler, but it's painful to imagine moving over all of the pages that I already have. DocuTools has lots of custom style names and has ...
-7
votes
0answers
48 views

Numerically solving a differential equation [closed]

Given the differential equation $𝑑𝑦/𝑑𝑥 − 4\sin(4/𝑥)\,𝑦/2 = 0$ and the intial condition $𝑦(−1.5) = 1$, solve it in the range {-1.5, 1.5}. a. Solve using Mathematica's own numerical ...
0
votes
1answer
43 views

Passing a function into another function that integrates the 1st function [closed]

for example I have a = Sin[t] and then I have f[a_] := Integrate[a, {x, 0, pi}] Will it work? Will the ...
-3
votes
1answer
56 views

(2^n)+1 writing prime numbers in list format [closed]

1<=n<=1000 in the range of 2^n+1 prime values ​​that make the number of n Write the code that gives the prime numbers using the Do, For, or While commands. (Note: To test whether a number is a ...
5
votes
4answers
90 views

Import every 50th record from a data file [on hold]

I want to import a really big data file which seems like it is too big for Mathematica. That's why I want to import the data in parts. For example, if I have 15,000 rows of data then I would read in ...
3
votes
1answer
32 views

Is there a way to automatically use triangular elements in ToElementMesh [on hold]

I have some simple code to generate a mesh over a rectangle. ...
0
votes
0answers
51 views

Can't get a good nonlinear model fit [closed]

I want to fit certain data that looks like this: data = {{0, -0.079}, {0.02, -0.083}, ..., {43.94, -0.025}, {43.96, -0.014}} but when I try to use ...
3
votes
2answers
101 views

Relations between two reciprocal partial derivatives?

My question is similar to How to get the partial derivative of the inverse functions? But they are different. If we have a function $z=z(x,y)$, we can calculate the partial derivative $\left.\frac{\...
1
vote
2answers
71 views

How can I iterate across a list of triples?

i just started to use Mathematica and I`m completely new to programming. So i'm some kind of noob in the purest form.. I'm trying to transform a coordinate system into a different one. I'm using <...
9
votes
2answers
198 views

Finding the path in a graph from A to B then back to A with a minimum of shared edges

the problem is to find cycle from A to B back to A, so that the path B-A would use minimum edges from path A-B. The graph is undirected and can have cycles. The paths don't have to be shortest, they ...
0
votes
0answers
27 views

Simple solve of function yields different solution than tutorial [closed]

I'm new to Mathematica and following some initial tutorials. When I replicate the exact code used in https://www.youtube.com/watch?v=O6h9_Xx-nLA (19:06), I however obtain different results. Here: <...
0
votes
0answers
30 views

Does CDFPlayerPro support evaluating code in a cluster?

Just like the title says, does CDFPlayerPro support evaluating code in clusters? I have a model developed on a laptop using 11.3 which would benefit from a cluster, but rather than buying multiple ...
2
votes
2answers
76 views

How to construct and plot the following accumulated list?

I have a list, say it is a = {1,3,3.2,3.9,4,4.4,4.9,5,7,8} To get the accumulate: acc = Accumlate[a] I want to plot the ...
0
votes
0answers
29 views

How to use the Mathematica [duplicate]

I am a new learner for Mathematica. I know just some basics of Mathematica, I can plot simple graphs. But, sometimes I have to plot some complicated graphs. Then, I am unable to plot that particular ...
1
vote
0answers
51 views

Colors in contours

When I want to draw a wide range of pictures,the value z=1 or z=-1 corresponds to plate patterns,I want it corresponds to one colour.This problem arises only when the scope of painting is ...
3
votes
0answers
72 views

How to get the executable out of a compiled function and run it in cmd

Can someone please guide how to run the function compiled by Wolfram Language in cmd independent of the kernel. It seems to export it into ...
0
votes
0answers
65 views

NDSolve boundary condition relating derivatives in different variables [duplicate]

I am trying to solve a wave equation (2nd order PDE) in z and t with absorbing boundary conditions, i.e. a boundary condition that relates the partial z and t derivatives. For this particular example,...
1
vote
1answer
42 views

Obtaining the vertex cosine similarity from a graph

Given a set of edges, how can the adjacency matrix of these edges be populated with each vertex pair's cosine similarity measure? Consider this edge set: edges = {TX -> R1, R1 -> R3, R3 -> R5, R5 ->...
0
votes
1answer
65 views

Integral doesn't evaluate as it must be! [closed]

i have this integral it must result in all constant values and the value of the integral its self which is Zeta[2/3] it can be done. ...
5
votes
2answers
77 views

Sub-subscripts in strings cause different spacings than subscripts

Spacing around subscripts within strings seems to work well: But the spacing around sub-subscripts does not: I did not manually add that space after the 2. How can this be fixed? Thanks!
0
votes
0answers
35 views

Finite difference code is producing an error [closed]

I used finite differences for mkdv equation but I get an error. how do I correct my code? ...
3
votes
1answer
45 views

Fixing different display colors within string

My question below is my attempt to reduce a problem I am having to the simplest possible version that will show the error I am trying to fix. I recognize that the coding looks tortured, and I will ...
6
votes
2answers
69 views

Store Dynamic-accessible hidden metadata in a cell

Is there a way to store metadata in a cell in such a way that it can be accessed with Dynamic? Think of e.g. how ExternalLanguage cells work. We can select whether ...
4
votes
1answer
82 views

How to safely forward/manage options between functions?

Algorithms can often be splitted into smaller and reusable functions (that's a good thing). However with this scheme I am frequently facing "option forwarding problems". Imagine that you have 2 ...
0
votes
0answers
31 views

Use non-rule elements in multi-page form

I am trying to figure out how to use non-rule elements to adjust the appearance in FormFunction[] while also using a multi-page form. I can use the following for ...
1
vote
1answer
57 views

Replace every n-th part of list [on hold]

I have a list: b = ConstantArray[1, 50]; And I would like to replace every say 5th element with 2: I came up with: ...
0
votes
0answers
24 views

What's LinkObject error about, and what may have caused it?

I've been running a simulation on a server, using parallezation, suddenly I got this error message: ...
0
votes
1answer
47 views
0
votes
0answers
42 views

NDSolve and Quantity[]

I'm working on a set of relatively basic ODEs of a physical pendulum and motor: $$\left\{\text{jb} \theta ''(t\text{s})+\text{rb} \theta '(t\text{s})+\alpha \sin (\theta (t\text{s}))+\mu \tan ^{-1}\...
2
votes
1answer
87 views

Importing and visualizing 4D data

I am very, very new to Mathematica (I downloaded it 1 hour ago). I have a set of 1000 rows, 4 columns data, in a CSV file: data My first problem is that I don't know how to select the columns in the ...
0
votes
0answers
59 views

A way to calculate colour from wavelength?

I'm trying to create a script taking my experimental values of measured radiance and turn it into xyz and rgb colour values. I import table with colour matching functions from here -http://cvrl.ucl.ac....
1
vote
3answers
165 views

How to substitute curly brackets with round brackets in a grid of list

I want to produce a table (or a grid) from my list of data, as follows: ...
2
votes
1answer
56 views

Gap Statistic Significance Testing with KMeans / KMedoids

Relatively basic question here about FindClusters / ClusteringComponents. So I have noticed that Mathematica has an option for ...
10
votes
1answer
385 views

Pascal records and Mathematica programming

Background: "experienced" Pascal-programmer (DOS-era, never got into OOP) proud owner of Mathematica ver 11.2 have used Mathematica for years to do my share of number crunching and plotting to ...
2
votes
1answer
25 views

How to export multiple column to excell from mathematica with each name at the sheet

I have a generated a dataset, name TRES. Its a data between wavelength vs intensity for different time. time varies from 0 ns to 5ns with an interval of 0.1ns. So there is a 51 no of set, and I want ...
1
vote
0answers
32 views

How is the PowerSpectralDensity function implemented? [closed]

I am working on a signal processing lecture for undergraduate students with Mathematica exercises/examples, and I would like to explain to them what happens when they run the ...
1
vote
1answer
46 views

RandomReal in combination with NormalDistribution [on hold]

I am normally not working with Mathematica, but I have to understand a code written in i! Can some body say what the arguments and parameters of code below say? ...
5
votes
1answer
2k views

Why is this recursive code so slow?

This code for the first five iterations the speed is okay, but after that the speed is very slow, I cannot understand what is wrong with this? Would you please help me fix it? ...
0
votes
0answers
47 views

How do I extract the value of a solution returned by Solve? [duplicate]

For instance, I have an equation to be solved: Solve[c == 0, c] And of course, the result is {{c -> 0}}. What I need is ...
3
votes
3answers
313 views

Finding the area between two curves with Integrate

I'm trying to solve and approximate the area between the two graphs. Right now, my functions are stored as f[x_] := 3 Sin[x] g[x_] := x - 1 and then I tried to ...
0
votes
0answers
30 views

Reading a chunk of data from a stream using Parallelization

I am trying to read a stream and perform some operations in parallel. Here is the logic of the code inside the ParallelDo: 1- Open stream 2- Read chunk of data 3- Close stream 4- Process the data ...
0
votes
1answer
35 views

Trying to select nth elements from a list [closed]

I'm trying to take the nth element of each sublist. Below is an example list: exlist = {{{1,2}, {2,6}, {4,1}}, {{2,3}, {3,1}, {2,4}}, {{5,6}, {7,5}, {6,7}}}; <...
0
votes
0answers
19 views

Gradient method in vectorfield on surface table does not work, module is slow

For teaching purposes I want to generate a vectorfield on a surface an visualize the path of the gradient method. The surface and the gradient are generated by ...
4
votes
1answer
118 views

Currents/voltages graph for an electrical circuit

I am trying to design the network graph for an electrical circuit. I have done this by hand so far. Here is the code for the voltages graph ...
4
votes
1answer
59 views

I want to place the edges of a Hamiltonian cycle

I don't understand why, but the GraphLayout style "CircularEmbedding" doesn't place the vertices/edges of a Hamiltonian cycle on the circle. Is there any way I can ...
0
votes
2answers
76 views

Result with assumptions contradicts previous result

Without assuming anything on the argument of the complex number inside the Gamma function ...
0
votes
2answers
90 views

How to animate a randomly updated plot

I have created a simple animation to explain to students how temperature affects the occupation of energy levels by using Animate to try to continually apply a ...

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