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0
votes
0answers
7 views

Numerically solving a system of two equation, one containing a log function

I am trying to solve those equations: ...
0
votes
0answers
8 views

grouping common powers of Bose operators

I compute a product of Bose operators and turn it into normal ordering using Boson commutation relations, e.g: ...
0
votes
0answers
15 views

Factorize a matrix that is associated to an image with RGB code

I have this image data and size: ...
0
votes
0answers
15 views

Set::setps: in the part assignment is not a symbol

I use a loop to create a set of matrixes Subscript[k[x, y], i], depending on variables [x, y]. Then I create a large matrix <...
0
votes
1answer
19 views

Clarification needed for two different D[…] operations

ClearAll[sus]; D[sus[i, t], t] /. i -> 1 generates (0,1) sus [1, t] And ...
0
votes
1answer
34 views

Define a function for symbols with UpValues

Suppose that we define UpValues for different symbols isSpecialFunction[N1]^=True isSpecialFunction[N2]^=True isSpecialFunction[N3]^=True I would like to make the ...
2
votes
1answer
19 views

Sort eigenvectors by eigenvalue and assign to variables

I have the following question: Let T = {{0, 0, 2}, {0, 0, 0}, {2, 0, 3}}, I know that its eigenvalues, in a decreasing order, are 4, 0 and -1. Mathematica displays ...
1
vote
2answers
43 views

QR decomposition using Gram Schmidt [closed]

First of all I don't want to use the reflection method. Only Gram-Schmidt. So here's the program for Gram-Schidt: ...
0
votes
1answer
24 views

Define a derivative-like function

I would like to define a function Cd[a_][expr_] which takes an arbitrary argument a and acts on the expression ...
0
votes
0answers
36 views

Can I speed up my tensor calculations?

I am running this code now for hours, which is not even that hard actually, but Mathematica seems to have troubles with it: ...
1
vote
1answer
33 views

Exporting selected columns of multiple table into a single Excel file

Please suggest how to export multiple tables in a single excel file. I am trying to use the code given below: ...
-1
votes
0answers
27 views

How do I align and fix these tabs? below is the code? [closed]

Please help align and fix the following tabs. Below is the link: https://kalumbila.com/project.html
1
vote
1answer
62 views

How to draw this figure and extract information out of it?

Consider a unit sphere. The cube of the maximum size that can be inscribed inside it has the vertices $ (\pm1, \pm1, \pm1)/\sqrt3 $. A tetrahedron can be created from this cube by choosing appropriate ...
2
votes
2answers
68 views
0
votes
0answers
21 views

Connect remotely to Mongo DB

I am trying to connect to a MongoDB remotely using Mathematica. DB Name: http://m0.lmfdb.xyz/ I went to the user mailing list where this code was posted to connect in Python. from pymongo import ...
0
votes
1answer
41 views

Symbolic evaluation expressions containing a user-defined function [closed]

I have a function F[r] = (-1)^(r + 1) Binomial[n, r]/r I would like to evaluate F[x+1]/F[x] for some arbitrary ...
-4
votes
0answers
34 views

Need to write a code using loops [closed]

Write a program that reads an integer from the user and determines whether it is divisible by 2 and 7 or not. Test your program using the following inputs: 12, 28, 42, and 63. Your output should look ...
1
vote
1answer
44 views

Save out plot and plot legend

I am attempting to save out a plot to .eps file, but cannot get the legend to come with it. Copying and pasting the image, saving as a JPEG and converting to .eps loses too much resolution for it too ...
6
votes
1answer
94 views

Is there a way to get tooltip for parts of a string?

Is there a way to get the tooltip to appear for parts of a string? ...
0
votes
2answers
45 views

Using function abbreviation yields different results from definition?

I'm not that great at using Mathematica so please bear with me. What I'm trying to do here is compute the coefficients of the metric tensor in 3D spherical coordinates, from which I'll construct the ...
0
votes
1answer
66 views

How to perform symbolic integration of six variable function?

I have a function of six variables in total - x1, x2, x3, x11, x22, x33 and I need to perform symbolic integration to get a symbolic expression. Before showing my ...
0
votes
1answer
50 views

Question about DSolve (nonlinear ODE)

I try to solve the following IVP (found in a textbook): $\frac{d^2y}{dx^2}=\left(\frac{dy}{dx}\right)^2$ with $y(0)=1$ and $y'(0)=1$. I use reduction of order. Say $u=\frac{dy}{dx}$. Thus $\frac{du}{...
0
votes
0answers
31 views

Problem with Syntax Error [closed]

I want to evaluate the following code: However, I do not understand why Mathematica insists there is no closing ")".
0
votes
1answer
28 views

Table returns different value depending on index

I have a problem, where I am trying to find the number of eigenvalues of a matrix smaller than 1. The matrix has a general form, given by ...
2
votes
0answers
44 views

Where can you get by walking half a mile?

I recently saw that Mathematica 10 introduced really nice tools for geography. I would like to use GeoGraphics to visualize all possible paths with a length of half ...
1
vote
0answers
35 views

Implementing the symbolic identity matrix $I$

I am working with symbolic tensors within Mathematica and I wanted to ask if there is a way to have a symbolic identity tensor.
0
votes
0answers
50 views

How do I find the root of a quartic equation? [closed]

How do I find the root of $\qquad x^4+x+c=0$ with $x$ as the variable and $c$ is constant.
0
votes
0answers
24 views

Evaluating functions at particular points

I'm a beginner with Mathematica, and I'm running into an issue that I don't quite understand. I define the quantities denom1 = (Sqrt[k^2 + m^2] - p)^2 - k^2 - m^2 ...
0
votes
1answer
50 views

Shortening the answering time?

I want to plot the fonction $(5,5)\ni w\mapsto \lambda(w,k)$ for $k\in\{1,2,3,4\}$ where $\lambda(w,k)$ is defined below on the penultimate line. The answering time looks infinite and I was not even ...
0
votes
1answer
81 views

Running Mathematica package on supercomputers by parallelizing it

a) I am thinking of installing Mathematica on supercomputers of my center. and running programs by parallelizing it for faster computations. But I was told that running Mathematica on supercomputers ...
2
votes
3answers
159 views

Transforming a 3D into a 2D Plot

I have a ListPointPlot3D in which all points lie on a plane. I'd like to transform it into a simple 2D Plot by looking at the points from an orthogonal direction to ...
0
votes
2answers
42 views

Solving equation for unknown and replacing it in second equation

I am new to Mathematica and struggling with its syntax. I have a set of equations, which I would like to solve for my unknowns. I would like to solve the first equation for the first unknown and ...
1
vote
0answers
29 views

ParallelTable never ends on simple ContourPlot loop

Context I am interested in solving Transient Gray Scott equations. Following the documentation: I define the equations ...
3
votes
1answer
99 views

How to unite polygons of the same color into a single polygon?

Let a partition of a planar polygon into colored polygons be given, i.e. something similar to We know the coordinates of the vertices and the color of each part, e. g. in such a way ...
0
votes
0answers
28 views

Minimum distance between a set of vertices in a 7 dimensional Hypercube [closed]

So I have eight 7 bit strings and I need to label it as the vertices of the 7-cube. Then I need to find two complementary vertices(two strings whose corresponding bits are inverted) and a bipartition ...
0
votes
0answers
26 views

C# and Mathematica mixed programming load package m flie

At present, we are trying to run Mathematica package with C# about m file, C# Code: ...
5
votes
2answers
122 views

Check if rows and columns of matrices have more than one non-zero element?

I am given a list of square matrices (with non numeric entries but abstract symbols which are assumed to take real values) and I want to write a function that returns True if the following condition ...
4
votes
1answer
40 views

Adding lists to specific elements in a list

I have compiled lists of non-diagonal and diagonal entries for a matrix. I'm trying to add elements from the diagonal-entry lists into certain entries of the non-diagonal lists. Is there a feasible ...
1
vote
0answers
40 views

Passing vectors into a Fortran function and getting out a vector

I am writing a Fortran function that needs to receive two vectors of reals, and as an output, returns a vector. The function could be for example the sum of the two vectors: ...
2
votes
1answer
48 views

Issues with Plotlegend

I'm making a 3D plot of the function En1 and I'm attributing its color to the sz1 function below, which contains values spanning from -1 to 1. ...
0
votes
1answer
30 views

Issue with threading matrices

I like this answer, which provides an "autoThread" function for more intelligent threading, but it doesn't work in this example and was hoping for a fix. So for this code: ...
0
votes
1answer
34 views

Programmatically defining variables

I seems as though what I am interested in is unconventional, but I am interested in defining a number of different variables programmatically. For example I can write a matrix of variables by doing: <...
3
votes
2answers
66 views
3
votes
3answers
128 views

How to draw borders around tiles of the same color?

I'm having difficulties with a project to show random tiles with a few random colors. Here's the code that I need to modify: ...
0
votes
0answers
58 views

Help me please help [closed]

Can you buy your dream car that worth \$46,000 after 40 months if (now) you invest an amount of \$30,500 to gain 12% annual interest that compounded each 4 months?
0
votes
2answers
44 views

How to create an infinite Table of numbers

I wish to create to generate the set $\{\pm \, 5^n : n\in \mathbb{N}\cup \{0\} \}$ and solve the equation $a+b =c+d$ for all elements quadruplets $a,b,c,d$ in the set which satisfy it. How would I go ...
0
votes
0answers
24 views

Display Kronecker product

is there a way to tell Mathematica to display KroneckerProduct[a,b] with the tensor symbol in general? So, in terms of Latex, a\otimes b ?
1
vote
1answer
53 views

NDSolve becomes very slow when the integration domain is 4 dimensional

I am trying to solve a PDE problem on a 4d manifold (3 space + 1 time). However, NDSolve becomes very slow when I jump from 3 to 4 dimensions. Here I want to integrate a simple ...
3
votes
0answers
34 views

Behavior of $MinPrecision seems to have changed between 12.0.0 and 12.1.1

I am running into a very weird bug where setting $MinPrecision to some value (in this case 200) has a very different and ...
0
votes
0answers
20 views

Vertex factor for effective field theory using Feynrules

Recently I have started learning "Effective Field Theory". As a part of learning, I was trying to calculate the vertex factor for a process where two unknown neutral spin-1 bosons $Y$ ...

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