# All Questions

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

I am trying to solve those equations: ...
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: ...
15 views

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

I have this image data and size: ...
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 <...
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 ...
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 ...
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 ...
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: ...
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 ...
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: ...
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: ...
27 views

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 ...
68 views

### How to change color of the points and remove the joined line in the given code?

I use this code ...
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 ...
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 ...
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 ...
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 ...
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? ...
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 ...
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 ...