All Questions

1
vote
1answer
114 views

How to plot this compound function?

I have a function w1(x1), w2(x2) and w3(x3), u1(x4) and u2(x5). Using these functions, I like to plot the deformed configuration of the structure, below is the undeformed configuration of the ...
0
votes
2answers
42 views

Automatic Manipulation of experimental data and plotting

I have experimental data which looks like this In the high positive and negative x-axis regions, my data is always linear, I want to extract the slope of data in these regions, take average and ...
1
vote
0answers
60 views

NBodySimulation

My question is about new NBodySimulation package in version 12. I figured out how to customize the basic functions "PairwisePotential", "PairwiseForce","ExternalPotetial"... The next unresolved issue ...
0
votes
0answers
26 views

Generating audio from integer list data

I have integer list data which I am outputting to MIDI format, however the list data range of values is much greater than the MIDI note range, so is it possible to use the min and max value in the ...
1
vote
1answer
60 views

How to make a diagram and get the exact intersection points at the same time?

Here is the code. A part of the diagram is not a function. ...
0
votes
1answer
32 views

How to deal with the derivative of an variable upper limit integration by the symbolic form?

I need a rusult with the following form D[Integrate[f[t], {t, low[x], upper[x]}], x] (*Out[]=-f[low[x]] (low^\[Prime])[x]+f[upper[x]] (upper^\[Prime])[x]*) My ...
0
votes
0answers
59 views

Rearranging a list of data

I need help for rearranging my data If I have data for 10 cases depends on L values (from 1 to 10) and every case has 5 columns (the first row has 5 values for L=1, the second row is for L=2, and ...
1
vote
1answer
25 views

Linear Programming using Maximize

I am trying to solve a more complicated version of the following LP problem: I have some constraint amounts a,b,c and two variables made of those amounts. I would like to find the best way to ...
2
votes
1answer
30 views

$2+2+\dots+2$ cycle conjugation classes of the symmetric group $S_n$

Command GroupElements[SymmetricGroup[4]] gives me all cycles of all conjugation classes. But I'm only interested in the 2+2 class ($2+2$ being one of the integer ...
2
votes
1answer
49 views

Problem finding separatrices for ODE system

I have a system of two ODEs for which I would like to plot the separatrices. I tried the very neat method given here by Michael E2. Unfortunately, that code doesn't work for my system since the ...
3
votes
1answer
70 views

Improving identicon graphics

This question has two parts, a technical part about graphics, and a creative part. I'll accept answers primarily re the first part. The application is to come up with graphical identicons to ...
2
votes
1answer
33 views

How can I fix an error when I try to draw a region function in a contour plot?

I am trying to draw a region function in a contour plot. My function has five variables and I want to reduce the number of variables by assuming some appropriate values for three of the variables. ...
4
votes
1answer
77 views

No shading in ContourPlot3D

Say you want to plot a horizontal plane using ContourPlot3D[x == 0, {x, 0, 100}, {y, 0, 100}, {z, 0, 100}] How to turn off the shading? I would like to have only ...
3
votes
1answer
40 views

How can I make a scatter plot from a matrix with many y-axis values for each x-axis value?

Consider matrix A = {{0, 2.54343, 3.566, 4.2323, 2.3434}, {0.1, 6.432, 4.6465, 5.656, 1.34}, {0.2, 0.3423, 1.6342, 3.323, 2.04}}; The x-axis values ...
1
vote
0answers
41 views

Separating periodic solutions from list of solutions in NDSolve

I am solving a second order differential equation using the following code ...
0
votes
0answers
35 views

Piecewise function to include SawtoothWave function

I am trying to write a Piecewise function that includes the SawtoothWave function. Can someone indicate how to do this, or if it is possible within mathematica? The piecewise code is here: ...
0
votes
0answers
28 views

How to collect a tensor in an equation?

Is there any way to collect a special tensor (for example the metric tensor) in a tensorial equation? I mean a command like Collect in the non-tensorial ...
3
votes
2answers
188 views

Help with coding a matrix

I have a $n \times n$ matrix $A$ with a full set of eigenvalues $\lambda$ including repetitions. I want to create the following $i \times i$ matrix: $$\left(\sum_{a=2}^i (a-1) |a-1⟩⟨a| \right) + \...
2
votes
0answers
26 views

Symbolic formula from GeometricScene?

I'm trying to solve the following problem with GeometricScene What is the shortest circular arc of which the altitude above its chord is one? I have the following code: ...
1
vote
0answers
39 views

Integration methods used by Mathematica [migrated]

Writing: Integrate[ArcTan[(E Cos[x] + Pi Sin[x])^2], {x, 0, 2 Pi}] I get: 2 Pi ArcTan[Sqrt[1/2 (-1 + Sqrt[1 + (E^2 + Pi^2)^2])]] I was wondering if anyone ...
1
vote
1answer
43 views

How to get a more efficient solution for the mode shape?

With 3 degrees of freedom m, k, and w ...
1
vote
0answers
39 views

How does Mathematica find the process parameter?

I want to know what kind of algorithm is used by Mathematica's Estimated Process. For example, we can estimate the parameter as follows: ...
4
votes
2answers
73 views

Table the LCM of an increasing list

I want to create a table showing LCM[1,2], LCM[1,2,3], LCM[1,2,3,4], ..., LCM[1,2,3,...,m]. ...
1
vote
1answer
26 views

ParametricRegion not recognising list of variables

I am trying to use ParametricRegion to plot some parametric equations that can be in various dimensions. The full code is as follows: ...
9
votes
2answers
514 views

Make symbols atomic, without losing their type

So, I'd like to define a matrix M, that does not decompose into it's constituents when I do things like Tr[M], but I also want it's type to be retained. (By type, ...
1
vote
1answer
92 views

Eigenvalue problem

my question is about solving an eigenvalue problem of the Helmholtz equation using sinc approximation $\nabla^2E + V (x) = \lambda E$ and $V(x)= X^2 / 2$ I have a problem in calculating the ...
9
votes
1answer
311 views

In a list with unique pairs {A, B}, how can I sort them so that the last B is the first A in the next pair?

list = { {4.8, 1.2}, {7.3, 3.1}, {3.7, 2.8}, {9.6, 1.3}, {4.8, 8.7}, {1.2, 7.3}, {5.3, 4.8}, {3.1, 5.3}, {3.1, 3.7}, {2.8, 9.6}, {1.3, 4.8} } Result after ...
1
vote
1answer
26 views

Editing the graph to become with animation

In the following code: p1=ParametricPlot3D[{ (3 + Cos[v]) Sin[u], (3 + Cos[v]) Cos[u], Sin[v]}, {u, 0, 2 Pi}, {v, 0, 2 Pi}] p2=ParametricPlot3D[{Cos[Sqrt[2] t](3 + Cos[t]), Sin[Sqrt[2] t] (...
7
votes
2answers
130 views

Animate a parametric curve

How can I animate the following curve? ParametricPlot3D[ {Cos[Sqrt[2] t](3 + Cos[t]), Sin[Sqrt[2] t] (3 + Cos[t]), Sin[t]}, {t, 0, 50} ] Can I also remove ...
3
votes
1answer
41 views

NodeJS external session not returning value

I have setup my NodeJS session and performed the following test. I evaluate the following commands in ExternalLanguage cells. <...
1
vote
0answers
25 views

Hyperlink to Documentation Pages

Is there a way to Hyperlink to a documentation pages. Since documentation pages are notebooks, does hyperlinking to these with file protocol opens them in the documentation center with all the ...
4
votes
1answer
78 views

Efficient way to sum over an index repeated more than twice

I'm looking for an efficient way of computing sums of the type $$D_{jk} = \sum_{i=1}^n A_{ij} B_{ik} C_{i}$$ for large numerical matrices $A$, $B$ and $C$. Here is a slow solution: ...
2
votes
1answer
35 views

Replacing a line by a cylinder

How can I replace the line in the following graph by a tiny cylinder? parametricPlot3D[ {CosSqrt[2]t, Sin[Sqrt[2]t](3+ Cos[t]), Sin[t]}, {t, 0, 100}]
3
votes
2answers
104 views

Efficient way to iterate over large list and check conditions

The problem I am trying to solve is how to assign charges to a number of particles based on some conditions on the charges. It is conceptually very simple but requires processing a very large list. ...
0
votes
0answers
29 views

Problem with numerical precision of the N command

I am trying to learn Mathematica. I found some unusual behavior with the N command. Here is my code. ...
3
votes
3answers
53 views

How to add a сolumn from one table to another?

I have a rather naive question. How does one add a column from an already existing table to another already existing table?
0
votes
1answer
39 views

Can't get Animate[] to work consitently

Wave on string from [0,L=10]. Endpoints fixed and initial conditions a double sinc: Ti1(x) = Sinc[3*(x - 7)] + Sinc[3*(x - 3)]. Initial velocity Ti2(x)= 0. Evaluating as expansion and trying to ...
0
votes
1answer
64 views

How to plot that function?

I have a function P which is dependent on x, I tried plotting the function but I am getting nothing in the plot. I am also interested in finding the roots of the equation. ...
2
votes
1answer
100 views

MMa version of $\LaTeX$'s overtilde doesn't look as expected

I am (mis)using Mathematica as a WYSIWYG LaTex editor. I want to put a (long) tilde over an expression. ...
1
vote
1answer
59 views

Apply a transformation to one sublist of a list

Say that I have a list of the form A={1,2,{{3,4},{5,6}}} I want to manipulate the first elements of the last sublist. For example, in the case of multiplication ...
5
votes
1answer
259 views

Operator currying: how to convert f[a,b][c,d] to {a+c,b+d}?

This question is related to this golfing question (but I'm not interested in golfing, only in functional operator composition): How can we convert f[a,b][c,d] to <...
0
votes
1answer
30 views

How to obtain the correct interpolation for the following data?

I have a dataset DistrTemp.dat. It represents a set of data in the form {{x,y,z,f[x,y,z]}}. Here, x defines a system, while ...
0
votes
1answer
31 views

Manipulation of a plot computed in several steps

the following test works for fixed parameter si: ...
4
votes
1answer
91 views

Selecting unique column position of a non-zero value for each row of a matrix

I have a matrix in this case of 3x11, but I want this to work for any dimension matrix. I want per row a column position on a non-zero value in that row, but that this value should be different than a ...
0
votes
0answers
55 views

Animated wrapping line and wrapping cylinder

I am trying to draw the following situation using any graphic program but I couldn't since I don't know how to make the animation. So your help is greatly appreciated. So my picture consists of two ...
0
votes
0answers
30 views

How to get some Gaussian distribution from image areas? [closed]

how to get some Gaussian distribution from some areas of an image. for example, I have a contrast or luminance channel of an image and I divide it into 12 areas, now I should get Gaussian distribution ...
-1
votes
0answers
33 views

Deriving a probability density function from data without interpolation

I have a dataset having the form {{x1, y1, z1, f[x1, y1, z1)}, ...}, correspondong to coordinates and values of the probability density of a distribution. I am ...
2
votes
2answers
38 views

Efficient ListConvolve over 3d matrix

I'm trying to find an efficient way of applying list convolve to a 3d matrix of 0 and 1, where about 5% of the matrix are 1, but the 1s may either be randomly placed, or grouped in one large ...
2
votes
1answer
69 views

Find Probability that Image Is Text

I can find out whether an image is text: ImageInstanceQ[img,Entity["Concept", "TextualMatter::m7642"]] And if an image is most likely text, I can find out the ...
0
votes
0answers
34 views

Interpolation of multidimensional data: some domains are lost

I am trying to make a reasonable interpolation of a dataset having the form dataset = {{x1,x2,x3,f[x1,x2,x3]},...}. I to the interpolation in the following way: <...

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