All Questions

Filter by
Sorted by
Tagged with
0
votes
0answers
30 views

How to convert this equation to a second order one in f?

This is a third-order differential equation. Is it possible to convert it to a second-order one by integrating it or any other way? I think it could be done by multiplying by some additional factors. ...
0
votes
0answers
34 views

Division algorithm problem that need to be solved by using procedure [closed]

My problem is; Write a procedure which finds the quotient and remainder of the division algorithm applied to two integers a and b. How can I use Floor to solve ...
5
votes
1answer
53 views
2
votes
2answers
286 views

How can I solve the Ramanujan problem by using Wolfram language? [closed]

The problem like this: find all integers n, 1 ≤ n ≤ 10, 000 such that n is the sum of two cubes of positive integers in two different ways. I want to solve the problem as a procedure in mathematica.
0
votes
1answer
28 views

assigning integers to inner lists

Consider a asymmetric list which has been obtained from a NSolve command ...
4
votes
2answers
70 views

Using the Range function with the Slot (#) function

I am writing a code to display longitudinal waves. I started with the following, filling the slots using the Range function. ...
0
votes
0answers
33 views

Trying to extract the Eigen values and Eigen vector of a matrix

I have a Matrix A, which is a function of ω. I wanted to find the eigenvalues and eigenvectors of this matrix, how to do it. I have used the EigenSystem function ...
3
votes
1answer
39 views

How to get Thick and Black contour line in 2d list contour plot?

I am trying to make contour plot of a 20*20 matrix using the function ListContourPlot. I want the contour curves to be thick and black at the same time. So I tried ...
0
votes
1answer
40 views

Trying to define a function using indexed variables

I have a list of indexed variables, for example xx={x[2],x[4]} and an expression which is a function of those indexed variables, say ...
0
votes
0answers
39 views

Simulating a bicycle going around a circle

I want to simulate a bicycle moving around a circle. Instead of graphs and calculations, I want to almost see an actual simulation of this happening. How could I do this? I tried looking up ...
1
vote
1answer
53 views

Bug in FindRoot?

...
0
votes
1answer
25 views

Deleting numbers from a list based on another longer list [closed]

I would like to delete all elements of a list that are equalled to any element found in a bigger list. For example, if I had A = {1,2,3,4,5} and B = {2,4,6,8,9,12} I would like to get C = {1,3,5} ...
1
vote
1answer
33 views

Extracting values from a dataset column based on key from a different column

Take a small dataset, for example a sample of the Titanic data: ...
5
votes
1answer
65 views

Is there a (simple!) way to convert all initialization cells of a document to normal cells?

I like to work with initialization cells. During the different stages of development of my notebooks, I however often need to change those. If they are scattered throughout the notebook, it is ...
2
votes
1answer
61 views

Reduce to Piecewise

There are some similar posts on SE, but none of them seems to exactly address my issue. I need to integrate a rather complicated function (over $x>1$) separately over two domains defined as ...
5
votes
4answers
840 views

Flatten an array

I have obtained an array of results as follows ...
0
votes
0answers
24 views

I can't exit Full Screen when I am pressing F12 [closed]

I use Dell Inspiron 15-5577. When I am holding F12, the screen just brighten. The software version I use is 12.0.0.0
0
votes
1answer
29 views

Sets of k expressions, being k a variable

I need to write something like Table[Subscript[A,i] = i, {i,5}] in order to define a set of expressions. All is OK with this, but if I try to left the number of expressions as a variable k... Table[...
3
votes
2answers
86 views

How to get the nth value of a function with arbitrary number of arguments

I know that I can define a function of a List and get the nth argument like: f[x_List]:=x[[1]]+x[[2]] What if the argument of ...
0
votes
0answers
27 views

Are these TransformedDistributions identical?

If A1 and A2 are independent random variables, and B1 and B2 are as well, then are the following TransformedDistributions the same? ...
0
votes
0answers
26 views

Printing problem Mathematica v12

After installing MMA v12 (Windos 7) I cannot print (using Print) on several printers, which work fine together with other programs. If a use ...
2
votes
1answer
38 views

Error using MaTeX, MaTeX::texerr : LaTeX Error: Missing \begin{document}

I've managed to install MateX with all prerequisites. pdflatex and GhostScript paths are correctly specified. I am able to load it into Mathematica. However, a simple command such as MaTeX[x^2] gives ...
1
vote
1answer
28 views

Changing Vertex Color and Coordinates From a list or vertex

I'm making a visualisation of an email network of a company. Each vertex represents a person and vertex color represents their position(BOD,CEO,manager,leader). The edges' Thickness according to ...
0
votes
0answers
23 views

How to select multi vectors with particular condition

I have a matrix as: a01={{225., 1, 2, 3, 4}, {225.5, 2, 3, 4, 5}, {226., 3, 4, 5, 6}, {226.5, 4,5,6,7}} And I want to choose head: ...
0
votes
0answers
28 views

Mmma connectivity . parquet. python

Is there any way to exchange data in binary format with python ? Example. a) I have data in Mmma and want to export them to make use in python ... b) Want to use Parquet format
4
votes
1answer
117 views

Solving the Stokes equation for planar Marangoni flow with FEM

Background I would like to numerically solve the stationary Stokes equation from fluid dynamics $\eta_i \nabla^2 \vec{u}_i - \nabla p = 0$ with the incompressibility condition $\nabla \cdot \vec{u}...
-1
votes
0answers
25 views

Huffman-encoding7decoding [closed]

Write two commands (or modules if necessary) for Huffman encoding and decoding. Inputs to the first module should be a character string and a coding table; the output should be a binary sequence ...
1
vote
0answers
23 views

What does this statement about congruential randomness mean in the documentation?

Reading through the random number generator guide on wolfram, under the methods section for the congruential method, it talks about the “Bits” option. Could someone explain what this means to me? I ...
2
votes
1answer
41 views

Solving complex trig quations - missing solutions?

{ Sin[Pi/2 + I*Log[2 + Sqrt[3]]], Sin[Pi/2 - I*Log[2 + Sqrt[3]]], Sin[Pi/2 + I*Log[2 - Sqrt[3]]], Sin[Pi/2 - I*Log[2 - Sqrt[3]]] } // FullSimplify ...
0
votes
0answers
18 views

Referencing a control from within a module

Below is a simple Manipulate that references a module via a button, which resets a slider and value. I would like to reference and reset the slider control for the slider "n" from within the module "...
0
votes
1answer
64 views

FindMinimum giving wrong answer

I have a very simple problem that Mathematica is giving a wrong answer to. I want to minimize the following function: $\frac{3+t^2+6\theta +3 \theta^2}{6 t^3}$ in $\theta$ and $t$. Now, plotting the ...
0
votes
1answer
29 views

Subtraction of vectors subtracts whole vector with individual elements

When I'm trying to calculate the value of DP, it subtracts the PCurrent matrix from each element of PGoal. What am I doing wrong? ...
0
votes
1answer
60 views

How to auto-rotate a MeshRegion?

I have a 3D MeshRegion region1 as below: ...
7
votes
1answer
317 views

Finding a parametric curve fitting a two-dimensional dataset

I have a 2-dimensional data set where I want to find the function that fits best the points. My issue is that I am looking for a function of the for $f(x,y)=c$ with $c$ a constant. I could not find in ...
1
vote
2answers
56 views

How to export a cell in Messages console to PDF?

Using V12 on windows. This is the problem. I am calling an external function (Rubi in this case, but it could be anything), which ends up printing a cell (image) to the Console. I simply want to ...
2
votes
1answer
40 views

Controlling Manipulate in cloud deployment

Suppose I want to create a web app which duplicates (for simplicity), something like Manipulate[Plot[Sin[n x], {x, 0, Pi}], {n, 3, 10, 1}] ...
5
votes
3answers
244 views

Defining a big matrix for iterative algorithm

I need to solve this system of equations with Seidel and Jacobi methods, so I tried to define a big matrix in Wolfram. I have read documentation, and I wrote the following command that should help me,...
0
votes
1answer
46 views

How do you typeset raised indices in Mathematica?

I'm trying to follow a book that uses the variable $x$ for dimension in cartesian coordinates and $x'$ for the polar coordinates. I'd like to use this typesetting in my Mathematica notebook so I don'...
1
vote
0answers
54 views

What is the best setup for creating WSTP Programs?

I am relearning C++ so I can create C++ programs and run them inside Wolfram Language. I am installing the environment for writing C++. Can someone suggest the best and minimalist one which works best ...
1
vote
0answers
34 views

Need help with While loop [on hold]

I'm trying to do the iterative jacobian method but I can't get the output. Any other alternatives using iterative jacobian would be highly appreciated. ...
1
vote
2answers
76 views

How to assign a constant value in a recursion relation

I use the code ...
2
votes
0answers
40 views

Better way to treat branch cut problem in Mathematica

Currently, Mathematica treats function which has branch cuts; $\log(z)$,$\sqrt[n]{z}$, etc, by taking its principal value. This may cause a problem in Contour integration when the path of integration ...
1
vote
0answers
30 views

Why do DynamicGeoGraphics and GeoGraphics not generate the same relief map?

Documentation indicates that DynamicGeoGraphics takes the same options as GeoGraphics, except with respect to projections. Thus, one might expect that given the same options both should produce the ...
0
votes
1answer
31 views

Extract variables from sum of unevaluted functions

I have sums of the form sum = a f[1,1,0] + b f[1,2,0] + c f[1,2,1] + ... It is always linear in f[a,b,c]. I would like a ...
3
votes
1answer
259 views

Finding local minima of an energy defined by integration

This question is also asked here and here. I would like to reproduce the two solid curves in Fig. 1a of this paper. The total energy is given in Appendix A, and the curve is obtained by minimizing ...
5
votes
7answers
1k views

Make a list of Fibonacci numbers less than 1000, whose index is in the form 3m+1. Verify that all these numbers are odd

I've been working on this for far too long with unsatisfactory results. And after losing all my hours of work around 4am thanks to a glitch in the program itself, I'm at my wit's end. It was ...
2
votes
3answers
70 views

How to save expression with its name

I want to save expressions as well as their names in a file. func[i_] := i; Do[func[i] >>> out.m,{i,1,3}]; The output is ...
0
votes
1answer
60 views

Find the points closest to and farthest from the origin for a region in $\mathbb{R}^6$

Given $A$ being the intersection set between $x + y + z + u + v + w = 1$ and $x^2 + y^2 + z^2 + u^2 + v^2 = 1$, find the closest and farthest points to the origin that belong to $A$ in the space $\...
4
votes
1answer
119 views

How to include conditional statements in NIntegrate?

I have a function g which is the result of another integrated function f. This function (f) ...
0
votes
1answer
35 views

unknown variable in a recursion relation

I have a code as follows ...

15 30 50 per page