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-2
votes
2answers
38 views

help with plotting functions in Block and ContourPlot3D

I have a question regarding Block. In Doc, Block[{x=x0,…},expr] suppose we have two functions in ...
10
votes
3answers
545 views

Merging 4 matrices to one matrix

I am struggling with the task to merge four matrices as presented below. Since the matrices A-D contain more than just four entries it would be too complex to do it by hand. Is there a simple or ...
0
votes
1answer
32 views

How to make Button print the last updated point?

I am trying to create a graphics that outputs the population of a city on the graphics that is clicked. The problem is that it is not updating the last point that is clicked. Please help. ...
-1
votes
0answers
30 views

Using Show to combine two plots made with DiscretePlot3D [closed]

I used DiscretePlot3D to plot my equation, but when I tried to combine two different plots into one, Show did not work. Do you ...
6
votes
2answers
107 views

Destructuring a list containing two items to use it as arguments to a binary function

I'm experimenting with the Through function. I suspect there is a way to use that function to obtain both the mean and difference of two values. But this doesn't ...
2
votes
2answers
72 views

Replace elements of a list if the conditional is false

There is a list: {1, {a, b, c}, 1, {1, 2, 3, 4, 5, 6, 7, 8}, {A, B, D, Z}} It contains sublists of different elements and several $1$s. The goal is to replace ...
5
votes
3answers
205 views

Making one list from two lists by grouping them in a special way

I have two lists: list1 = {{{x1,x2},{x3,x4}}, {{x5,x6},{x7,x8}}}; list2 = {{{x9,x10},{x11,x12}}, {{x13,x14},{x15,x16}}} I need to join them to get one list: <...
2
votes
0answers
58 views

Why is Log[8 E^(3 Log[0.5]) != 0 [closed]

My wife and I have tried to calculate Log[8 E^(3 Log[0.5]) on a TI-Nspire and we got the result -8E-14. We have changed th settings of calculation to Exact and the result was 0 (correct) If I use ...
1
vote
1answer
29 views

Converting String in “Data” Format within Mathematica [closed]

Hi I have a simple question. Given a random string in the format accepted by the Import[fileWithString, "Data"] i.e the file contents being ...
3
votes
0answers
25 views

Lightweight Grid: transfer a file to the master kernel?

I am trying to run code on a Lightweight Grid using ParallelDo. I have ~300 jobs that each take ~20 minutes to run and produce ~8 MB of data, and I am using a ...
0
votes
0answers
49 views

Having trouble understanding code to do formatting with MakeBoxes

Can anybody explaining this code? ...
0
votes
0answers
44 views

How can one combine multiple DensityPlot3D plots so they are all equally visible in the final plot?

How can one combine multiple DensityPlot3D plots so they are all equally visible in the final plot? Here is an example: ...
1
vote
1answer
57 views

Finding frequency of oscillation of an particle by Fourier analysis of the trajectory

I am trying to find the resonant frequency of a particle by Fourier analysis of the trajectory. Here is the data file. ...
0
votes
1answer
88 views

Plotting eigenvalues

I am trying to reproduce figure 10 in the linked paper. The authors have used Matlab bvp4c function to find multiple solutions for the system of ODE and then carried out the stability. Here is my ...
1
vote
0answers
42 views

How to find the derivatives from Solve after obtaining 6 complex solutions?

I have a 3x3 matrix. By setting the determinant to 0, I find the values of w in terms of ka and graphed the complex solutions. m, M, k, l are constants: ...
0
votes
0answers
22 views

Standard Error not right with Linear Model Fit [closed]

I tried using linear model fit according to the example found here https://reference.wolfram.com/language/ref/ConfidenceLevel.html I noticed that ...
1
vote
1answer
36 views

Force UnitConvert to display the proper unit prefix and return inexact quantities?

I'm experimenting with units: UnitConvert[1/Quantity[2.0, "GHz"]] 5.*10^-10s ...
0
votes
0answers
48 views

Obtaining the results of tagged cells in a notebook from another notebook

My objective is to read the results of several tagged cells in a notebook NB1 from another notebook NB2. Following the ...
8
votes
1answer
257 views

Integrate over a region

I am trying to calculate a integral over a region defined by But I dont really know how to do it, I dont know if I have to work in cartesian coordinates or polar coordinates. The function that I ...
1
vote
0answers
80 views

Code doesn't run on my system but runs in another system

I have an issue with Mathematica. I have some code and its answer. When I run the code on my system, it doesn't work. The person who wrote the code believes that is correct, and I agree. I tried to ...
-1
votes
0answers
45 views

Converting an image of a plot to a plot?

Does Wolfram have the ability to (attempt to) convert an image of a arbitrary plot on the web, say: to its corresponding Wolfram representation (in this case:...
6
votes
2answers
150 views

Build a matrix from the coordinates of its elements and complete it with zeros

Suppose that I have a data set data (input): ...
0
votes
0answers
44 views

Comparing two methods of integration [closed]

Given two tolerances (like 10^-3 and 10^8), how can I compare accuracy of the two methods (explict Runge-Kutta and Adams) for the following system ` ...
1
vote
0answers
56 views
+50

Loading Animation in Manipulate

I'm using Manipulate together with CreateDialog to run a ListPlot whenever I click on a ...
4
votes
3answers
117 views

How to implement an integration filter on arrays?

I have the discrete integration filters: $$y(n) = Ax(n) + By(n−p) , \text{$A$, $B$ real constants, $p$ positive integer}$$ EDIT: in the initial version of this question I focussed only on the case $...
1
vote
0answers
14 views

Exporting output from many NDSolve's to common .txt [duplicate]

Let there be the following working example ...
2
votes
1answer
29 views

how to display Sin[Subscript[\alpha,i]/2] as $s_{\bar{\alpha}_i}$ using e.g., Makeboxes?

Update: the following code proposed by Lukas works perfectly. I have tested both fraction or $a/b$ form, both work. I have revised the code a little bit, to make it more flexible: ...
0
votes
1answer
39 views

How to get the overlap's percentage that occurs between 2 circles or among more than 2 circles?

The following code draws the following circles; ...
0
votes
0answers
54 views

Smoothing out oscilations from data [closed]

Could anyone please help me with smoothing my data. The list plot of the data looks like this: My goal is to create a list plot without those oscillations. Preferrably with the final curve being the ...
0
votes
0answers
17 views

NMaximize scrambles constraints

There have been lots of questions around regarding the issue that NMaximize/NMinimize may give results - or at least evaluate ...
0
votes
1answer
30 views

Drop doesn't work with Dynamic lists

So I have this code right here. ...
0
votes
0answers
32 views

Stiffness Matrix Assembly in FEM [closed]

Can anyone suggest a fast and efficient global stiffness matrix assembly code in FEM?
1
vote
1answer
57 views

Plotting error from Einstein-Podolsky-Rosen paradox plot

I am very new to Mathematica, so I might be doing something dumb here. I'm trying to make a graph of the following code and it keeps on giving me an error ...
0
votes
1answer
38 views

mathematica stop working after running some .nb file and close or save the file

Bug fixed in 8.0.4 for Chinese edition only, generally fixed in or before 11.3. I'm using version 7 on Windows. After I running one .nb file and just want to ...
2
votes
3answers
47 views

Changing Y-Axis to “Billions of Dollars”

Is there a way to change my bar chart's Y-axis from powers of 10 to "billions of dollars"? For example $100,000,000,000 should read as ...
3
votes
0answers
39 views

StreamPlot hangs if streamPoints are outside the range specified

Is this a know issue? The following MWE works and gives plot immediately ...
1
vote
0answers
19 views

How to estimate parameters of TransformedProcess?

Let's say we have the following time-series. ...
0
votes
1answer
48 views

Retrieving the evaluation result of an Initialization Cell in a notebook `nb1` from another notebook `nb2`

I have a very long code in a notebook nb1 in which all the initialization cells are tagged. I have another notebook nb2 where I ...
0
votes
1answer
54 views

A single expression that performs substitution and simplifies a trigonometric form

I'm very new to Mathematica. I searched through the online documentation, but I don't understand why it realizes that $\sin(n\pi)$ for $n\in \mathbb{Z}$ is $0$: ...
1
vote
1answer
31 views

Extra white line in densityplot's output

How can I remove the white line in $y=0$? This is my code: ...
0
votes
1answer
33 views

How to solve an under determined system for a ratio of variables?

I have two equations in 3 variables a2, b1, b2: ...
1
vote
1answer
61 views

Track the location of of dot from noisy image

https://imgur.com/a/SnTYESG (subtraction between the image) https://imgur.com/a/ZdOS5wf (orignal image) From the original image, since my CCD camera is bad, I cannot really see anything. However, ...
1
vote
1answer
41 views

Writing code to produce continued fractions

I have been trying to create a continuing fraction to help prove the theory about any rational number: a/b being able to be written as a continued fraction where the remainders found in the Euclidean ...
1
vote
1answer
33 views

How to use FirstPosition in compiled function

I am trying to compile something similar to the following: test = Compile[{{data, _Real, 1}}, First@FirstPosition[data, _?(# > 0 &)]] However I get the ...
0
votes
1answer
69 views

Mathematica derivative not matching when I take derivative by hand

I want to take the derivative of this with respect to eta: fabc = 1/2 (-3 + 27/(2 + x)^2 + (1 - 1/(1 + (-1 + x) c[eta/cc])^2)/ c[eta/cc] + 2 Log[x]) Here I ...
1
vote
1answer
43 views

Plotting solution of an integral

I have used below code to plot the solution of an integral, but the code doesn't return anything. Could somebody please help me in this regard? ...
3
votes
1answer
64 views

Finding line that each n value is on

This code produces straight lines, I'd like to find which n values are on which of the lines: ...
2
votes
2answers
26 views

Count number of individual operations

Im interested in counting the number of operations required to evaluate a given formula. Let me give you an example. Lets say I have entered the expression $\dfrac{\operatorname{Sqrt}[\operatorname{...
0
votes
0answers
16 views

Estimate the Hidden Markov Parameter while keeping some of them are same

How can I estimate the hidden Markov model while using the same value for some of parameters? First, let's get test data (sorry, messy!) ...
6
votes
1answer
163 views

Strange result for sum $\sum _{k=1}^{\infty } \frac{\sin (k (k-1))}{k}$

In this sum over $k$ Sum[Sin[k (k - 1)]/k, {k, 1, ∞}] the result still containes the summation index $k$. ...

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