1
vote
0answers
4 views

Reinstalling Mathematica pro on the SAME computer

I am currently wiping my ENTIRE hardrive and reinstalling Windows on my (currently very slow) laptop. However, I don't want to lose my expensive version of Mathematica, and it looks like Wolfram is ...
0
votes
1answer
8 views

Graphics3D plot of group of Vectors

I am trying to overlap 2 different Coordinate Systems (C1,C2). I want it to be visually pleasing but it is increasing the length of code I tried ...
1
vote
0answers
6 views

TreeForm outputs different results for the same imputs but why?

First of all, please look at the below inputs and outputs: ...
0
votes
1answer
19 views

Quartic function from data

I am studying something about interpolation. I have a function that is a power x function ($f[x\_]:=17000x^{-1.85}$). From this function I got a list with coordinates for X and Y ($data2$) With ...
1
vote
1answer
21 views

Deleting circular regions from a larger Circle

I am trying to determine how the Dirichlet eigenvalues of the Laplacian of a circular region change. I would calculate the principal eigenvaluen of this image, and gradually decrease the radius of the ...
-2
votes
0answers
19 views

Simple qualitative sketches in Mathematica [duplicate]

I have always used Inkscape for sketches like the one below. Nonetheless, I am pretty certain that Mathematica is capable of creating something similar. How would I ...
0
votes
0answers
14 views

How to type greek letters on mathematica.stackexchange [migrated]

I usually ask questions on this website, and many of them contain greek letters in the code part. For instance: \[CapitalTheta]=0 After a while, someone edits ...
0
votes
0answers
19 views

Plotting topological defects with VectorPlot

I have been trying to create a table with the graphs of the lowest winding number topological defects that can appear in a nematic Liquid Crystal. That is what I have been able to do so far: ...
0
votes
0answers
24 views

How to pass variable to rule [on hold]

To export figures with specific font family and size, I define the following: LaTexFonts = {LabelStyle-> {FontFamily-> "CMU Serif", FontSize-> 14}}; Now ...
1
vote
1answer
32 views

Is there an equivalent to Mathematica's ToString in R for use with RLink?

x = "vvvv" REvaluate["f(\"vvvv\")"] (*works*) Want to replace vvvv with x: ...
1
vote
1answer
57 views

Why does Show ignore the option Joined -> True

I have this code: ...
0
votes
0answers
26 views

What are the differences between Clear, Remove, ClearAll, Unset and TagUnset, when to use which?

What are the influences of these operations on things like UpValues, DownValues, OwnValues and whether the kernel knows the symbol? When do I use which? I know ...
0
votes
0answers
15 views

How to resolve this issue related to Conjugate?

When I perform the vector multiplication given below FullSimplify[{a,b}.Conjugate[{a,b}]] I am getting the result as I expect ...
2
votes
2answers
39 views

How to transform the $y$ values in a list of $(x,y)$ pairs [duplicate]

How can I transform data = {{1, 0}, {0, 1}, {1, 1}} to {{1, f[0]}, {0, f[1]}, {1, f[1]}} This is similar to ...
0
votes
0answers
28 views

ParametricPlot3D step size

I tried to use ParametricPlot3D which appears in the kernel, such as; ParametricPlot3D[{xALL, yALL, zALL}, {ξ, 0, 5}, {η, 0, 3}]; but here parameter's step size ...
-1
votes
0answers
22 views

SparseArray Band with Array [on hold]

Probably a very simple problem : Why do I get z^2 and not z, and in the other case it works with a number ? Thanks, Edit: Copyable Code ...
0
votes
1answer
24 views

How to pair elements of a nestlist? [duplicate]

I have a this list for example expdata={{49, 50, 51, 52, 53, 54},{0,3,5,2,0,1}} and I want to rearrange it like this ...
2
votes
2answers
54 views

Henon Map Fixed Points Plot versus Iterations and Plot of the Map

For the Henon Map: $$ x_{n+1}=y_n+1-αx_n^2, \quad y_{n+1}=β x_n$$ I would like to discover period doubling bifurcations by varying the parameter $α$ and plotting $x_n,y_n$ versus the iterations $n$ of ...
2
votes
0answers
22 views

How to deal with tensor argument in LibraryLink?

For the Bézier surface, which owns the following matrix definition: $$\begin{align*} \mathbf{S}(u,v)&=\sum_{i=0}^m \sum_{j=0}^n \mathbf{P}_{i,j} B_{i,m}(u) B_{j,n}(v)\\ &=\small \begin{...
0
votes
0answers
7 views

Any theorem which specifies the state (with energy $E$) with maximum entanglement [migrated]

Does there exist any theorem in quantum information which states that the particular state with energy $E$ is the state with maximum entanglement (or discord) among all possible state with the same ...
3
votes
1answer
147 views

Quick way to generate the Shepp-Logan phantom

I have some very old code for generating a Shepp-Logan phantom: ...
2
votes
0answers
66 views

Fan beam tomographic projections in Mathematica

I am embarking on a little project to redo some of my old MATLAB image processing code in Mathematica. I am particularly interested in tomography, and I know of the ...
0
votes
0answers
26 views

What does it mean that “there are no significant digits to display”?

So I substitued with the following values in my function T(x,n) and it gave me this red box with the value in the picture. When I hover over it, it tells me that there are no significant digits to ...
-3
votes
0answers
47 views

Quaternary drawing [on hold]

I have these data and I want to draw such figure in mathematica. any one can help me? my data: ...
1
vote
1answer
27 views

BSplineFunction defies numerical solution

I am trying to find an intersection between a straight line and a BSpline. The lines: ...
2
votes
0answers
31 views

A bug of PrincipalValue?

This question is related to this one, I encountered some weird outputs when trying to solve it. Here is the code: ...
-1
votes
3answers
56 views

How to use SwatchLegend in Show? [on hold]

Let us suppose i have two graphs for sequences A and B as follows ...
3
votes
1answer
29 views

License issue when USB-LAN stick is connected.

I have mathematica installed on my laptop which only have a wifi card. When I connect a USB-LAN adapter, even if it is not connected to the LAN socket, mathematica complains that the license is ...
0
votes
0answers
23 views

PlotRange -> All for Show [duplicate]

I want to fit a gaussian function to a data below: ...
1
vote
1answer
51 views

Defined a function but it doesn't seem to work

I'm trying to implement the line-crossing algorithm on Mathematica and I seem to be having trouble getting it to work. More specifically, I would like to know what is causing the function to not ...
2
votes
1answer
64 views

difference between FullSimplify and Simplify

I have a problem to dinstinguish the following two mathematica codes, the only difference is the first use FullSimplify and the second is Simplify. but the results are totally different. what is wrong,...
1
vote
1answer
26 views

Converting a list of lists of indices into a sparse matrix of ones and zeros

I have data formatted like {{a,b},{c,d},{e,f}} where each entry is an integer. I need to turn this in to a sparse array with entries ...
-1
votes
1answer
25 views

Proof The union of an infinitely countable set and an element is countable [on hold]

If $A$ is countable infinite set and b $\notin$ $A$, then $A$ $\cup$ {b} is also countable. I thought of starting of saying lets assume $A$ $\cup$ {b} is countable and show that $A$ is a subset of it ...
2
votes
2answers
70 views

How to use NestWhileList with a function of two variables

I want to iterate a function of two variables in NestWhileList. Obviously it will need a termination condition. For example imagine I have this function: ...
2
votes
1answer
81 views

Python Convolve2D functionality in Mathematica

I am new to mathematica. I am looking for an alternative for scipy.signal.convolve2d. I did find functions like ListConvolve, ...
0
votes
0answers
52 views

Complex Analysis with MATHEMATICA [on hold]

I am interested in chapter 21 of the book: Complex Analysis with MATHEMATICA by William T. Shaw. chapter 21 - Conformal mapping II: the Schwarz—Christoffel mapping pp. 451-472 I'm not able to get ...
0
votes
0answers
34 views

Putting constraint on a replacement rule

I am a neophyte in Mathematica programming and your help is appreciated. I'd like to restrict the values that a parameter can take. These are my parameters ...
1
vote
3answers
69 views

Evaluating $\int_0^\infty dx /{(x^2-a^2)^2+b^4} $ returns a negative number

I am trying to evaluate $\int_0^\infty dx /((x^2-a^2)^2+b^4)$. And I seem to have an error that I cannot detect. Using ...
0
votes
1answer
25 views

solving a non linear (log-linear) recurrence relation

I'd like to solve the recurrence relation $$\begin{align*} f(n+1) &= 2 f(n)^2 h(n) \\ h(n+1) &= h(n) f(n) \\ f(2) & = h(2) = 2 \end{align*}$$ for an explicit solution for $h$ and $f$. So ...
1
vote
0answers
47 views

Why does DeleteDuplicatesBy fail?

This is a pretty straightforward code. I just want to delete duplicates based on the final entry in each row. I have evaluated very similar numbers with no problem. ...
7
votes
1answer
412 views

Data extraction from a picture of a graph

How can I extract data from this picture of a graph? i = Import["http://i.stack.imgur.com/Ac8m0.png"]; The caption of the picture reads: " Two-dimensional ...
3
votes
0answers
36 views

Hide Notebook scrollbars

Is it possible to hide the scrollbars from the notebook windows while still being able to use the mousewheel to scroll? Since I never click on the bars themselves they're just a waste of space. It's ...
0
votes
0answers
34 views

Easier way to input Dynamic matrix?

I've only been using MMA for a month, and I'm working on making interactive Linear Algebra examples that will be used online for students. Right now, for inputting numbers into a matrix, I've been ...
0
votes
1answer
57 views

Visualization problems [on hold]

I am visualizing 1-dimensional curves that are periodic. Due to periodicity, extending the domain should result in the curve being retraced and therefore remaining unchanged. This doesn't seem to be ...
0
votes
1answer
50 views

How can I get the differences of all elements of list? [duplicate]

I want to get the difference of all elements of a list for example: $L=\{1,2,3,4,5,6\}$ for any $i$ and $j$ $\in L$ return the differences, for example for the first element $1$ we get the difference ...
0
votes
0answers
31 views

Drawing Arrows to connect points from two separate data sets representing coordinates

I have 2 separate excel files that I'm importing into Mathematica. Each excel data file has numerous rows of data containing a coordinate of three columns (x,y,z). I have been able to plot these ...
0
votes
0answers
54 views

Henon Map Equation Trekker

I am trying to make an Equation Trekker for the Henon map in the following way: ...
3
votes
0answers
35 views

High CPU load for dynamic classification

I encountered some issues with extremely high CPU load when I tried to classify live images (using Dynamic and CurrentImage[]). ...
0
votes
0answers
50 views

Eigenenergies of a symmetric tridiagonal matrix [on hold]

we consider the time independent Schrodinger equation (TISH) where we want to calculate the first few instantaneous eigenergies. Discretizing space we get : So we can rewrite the TISH as, (where ...
0
votes
0answers
38 views

Simplify: Why does it miss this simple one?

I got a result with the expression ...

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