2
votes
1answer
238 views

ParametricPlot3D doesn't appear

Here I have one simple system solvable with NDSolve. I don't know why ParametricPlot3D doesn't present trajectory in space. I have solutions for x[t], y[t] and z[t] ...
6
votes
2answers
254 views

Cannot Get Numerical Results to Match

I try this numerical summation (in two parts) ...
1
vote
1answer
106 views

Can't see updating performed by NMinimize[…,StepMonitor->(…)] outside of Button in which it's called [duplicate]

I've made a peak-fitting GUI in which I have a "Fit" button that, when pressed, calls NMinimize[...,StepMonitor->(step++)] to minimize a sum of squared ...
1
vote
1answer
154 views

Manipulate not accepting default values

I have pasted my Mathematica code below. For some reason, the default value for h, or Δx, while set to 4.5 in the code, keeps displaying at -4 instead. I have been over and over this example, and I ...
5
votes
1answer
172 views

Generating replacement rules programatically

I would like to generate sets of replacement rules programatically for predefining some permutations. So a function ...
0
votes
1answer
183 views

Showing steps Mathematica uses for Resolve[ForAll[…]] [duplicate]

I have a quite complicated function of 2 variables: ...
10
votes
4answers
177 views

How do I evaluate the terms in an expression, but not the expression itself?

I am trying to write a set of homework questions. I would like the output to evaluate the constants but not the sum, so that I may present the homework question as something like this: ...
0
votes
1answer
94 views

Possible to use Manipulate in GUIRunModal?

Is it possible to use the widget created by Manipulate within GUIRunModal? I intend to run the file using ...
7
votes
2answers
282 views

Why does my matrix lose rank?

I want to check the rank of a matrix for observability, but Mathematica loses a rank if the matrix contains very large numbers. Let's say my matrix is ...
2
votes
1answer
290 views

How do I add a color bar to a 3D plot?

I tried Plot3D[Exp[-x^2 - y^2], {x, -2, 2}, {y, -2, 2}, ColorFunction -> (ColorData["TemperatureMap"][#3] &), PlotLegends -> Automatic] in an attempt ...
0
votes
1answer
314 views

Applying l'Hôpital's Rule to NDSolve with Piecewise Function

OK, so I've been working on this problem for over a week and it's driving me crazy. I'm trying to solve a system of two differential equations in $x(t)$ and $y(t)$ using a "time-elimination method," ...
1
vote
1answer
166 views

Use of Manipulate in CDF documents

I am trying to publish a cdf document, but I'm having some problems with the function Manipulate with this code: ...
-1
votes
1answer
114 views

Dynamically show a specific number of the fractional part's digits

What is the fastest way to cut off all n z digits of the fractional part of a real number? (For example 12390.20934230) I came up with this so far: ...
2
votes
0answers
40 views

Plot3D has a break in the center of the plot [duplicate]

I am trying to plot a relationship using Plot3D and for a reason I cannot figure out the function is not evaluated in the middle of my range. If I take a 2D slice ...
1
vote
1answer
124 views

Why Solve and Simplify give different results? [closed]

I want to solve the following equation y == (1/(1/4 + y) - 1/(3/4 - y))/((1/4 + y) + 1/(3/4 - y)) I tried ...
13
votes
1answer
506 views

Changing line thickness without changing line length

Is there any way to change the thickness of line without changing the width? For instance, the following example shows that as thickness increases, the white gap decreases. Is there any way to ...
0
votes
1answer
164 views

Construct file names using a number and a string prefix [duplicate]

I'm trying to append filenames with Mathematica, and cannot do it. The output of my calculation are two lists : X and Y, ...
3
votes
1answer
146 views

Manipulate for probability distribution with multiple parameters, kernel smoothing

I'm looking to use the Manipulate command to take a distribution with multiple parameters (e.g., mean and sigma for the normal), generate some variates, then plot ...
3
votes
2answers
110 views

CommunityGraphPlot doesn't size

When I need to plot a 'large' graph with CommunityGraphPlot the output is always sized at the Mathematica default value. The Graph object itself can be resized with ImageSize option. However that ...
4
votes
3answers
165 views

Text Annotation Disappears in Wrapped 3D Graphics

In a 3D graphic, if I wrap a figure, for example, ...
4
votes
1answer
106 views

How can I highlight the vanishing-partials in an interactive 3D plot?

I am using Manipulate and Plot3D to plot a function with two real variables and two extra parameters. ...
11
votes
1answer
186 views

Time range selector à la InteractiveTradingChart

I have time series data and I would like to interactively select a part of it. This problem is beautifully solved in the lower part of the InteractiveTradingChart command: I would like to be able ...
4
votes
2answers
3k views

How to use a 3×3 covariance matrix to plot an error ellipsoid?

I have a 3×3 error covariance in Mathematica, but I don't know how to use it for plotting the error ellipsoid. It would be great if you can show me how I can do that for the below covariance matrix: ...
1
vote
1answer
113 views

Using With in combination with Graphics [duplicate]

Assume that we are given a symbol p={x,y} which should represent a 2D point. If x and y have ...
3
votes
1answer
376 views

Exporting a Video of a Simulation of Pendulum Motion

In a series of previous questions, I asked how to solve a series of differential equations describing a series of coupled pendulums, and then how to plot this data by coloring the different pendulums. ...
3
votes
2answers
405 views

Save variables values and definition

I used to do a lot of programming in R and recently switched to Mathematica. One thing that bothers me is that I haven't found a way to save variables, their values and definition! Let's look at an ...
0
votes
1answer
66 views

Plot not displaying [duplicate]

I'm trying to perform a basic plot to show that two equations align, but I'm not getting any results. Plot[{[Pi]*Cos (3 x - [Pi]), [Pi] * Sin (3*[Pi] - 3 x)}, {x, -3 [Pi], 3 [Pi]}] To me this seems ...
0
votes
0answers
177 views

Fitting a theoretical density function with log-return sample

I am working on a exercise to fit a theoretical density function,presented below, with log-return series of a stock. $\frac{1}{2}a e^{a(x-\mu)} \quad \text{if x } < \mu $ or $ ...
4
votes
1answer
409 views

Show doesn't show all the plots

I try to combine three list plots with the Show command. Here is the first one: ...
8
votes
2answers
3k views

Increasing the thickness of line in plot legend

I've been using the shiny new legends in V9 for my plots. However, I usually increase the Frame/Axis ...
2
votes
2answers
214 views

Exporting arrays for storage [duplicate]

I have a set of arrays I would like to output to some file ArrayStorage.txt s.t. these arrays could be read-in to a separate notebook on a separate kernel. Is ...
2
votes
1answer
390 views

Volterra integral equation : 'literally match the independent variables' message

I want to solve an Volterra type Integral equation, and as a practice I entered the following code to my mathematica: ...
12
votes
3answers
358 views

How to memoize a function with Options?

Consider the following modified fibonacci function: ...
3
votes
1answer
337 views

BarChart and Log Scale results in different bar origins

I want to create a bar chart from two different data sets. ...
5
votes
3answers
664 views

Using PlotLegends

Please don't answer this with "Just trash PlotLegends" or anything like that as I have tried homebrew solutions. I keep running into problems which I can't debug as ...
0
votes
1answer
532 views

integration on real domain only!

i am trying to integrate a real valued function. For some reason, Mathematica gives an answer in the complex domain. I'd be grateful for your answers. Here is the integral: ...
27
votes
5answers
2k views

How to efficiently find positions of duplicates?

Is there an efficient way to find the positions of the duplicates in a list? I would like the positions grouped according to duplicated elements. For instance, given ...
3
votes
3answers
165 views

Dynamic application of several polynomials

I know how to get the 'resulting image' (y) from the application of a certain function (f) (here represented as the coefficients of a polynomial) over a certain interval (x): ...
0
votes
1answer
296 views

How to define a fixed length vector in Mathematica?

I would like to define a 3-D vector as say v={x,y,z}, but I want it to have a fixed norm, say a unit norm |v|=1. How do I impose this condition on v.
0
votes
1answer
149 views

High quantum harmonic eigenfunctions?

How to obtain high quantum harmonic eigenfunctions? Everything works until, let say 65th eigenfunction, but for higher eigenfunctions values are too high. My code ...
1
vote
1answer
129 views

Unwanted hold in recursive function

I have a function (let it be called f) that does something useful for me and I want to be able to apply it to the elements of a list regardless of their depth and keep the list structure. For example ...
-4
votes
2answers
176 views

how can i convert data into string format? [duplicate]

I have nested-lists in number format,like data={{1,2,3},{2,{3,4,50}},{4,5,6},{3,{3,{5,6}}}} I want to convert each number into ...
3
votes
1answer
143 views

How to change texture of chart bar?

Is there anyone who know how to make diagonal lines inside the chart bar like the below picture?
2
votes
1answer
227 views

How can I prevent these warnings while using ParallelTable

I have this code to find all the permutations of a set of letters that form legal words. ...
5
votes
1answer
425 views

How do I put an image on the complex plane?

I watched this video and became interested in transforming an image. But I have no good idea on how to embed an image in the complex plane using Mathematica. I have a method that seems to work, but ...
3
votes
2answers
475 views

For loop with steps other than 1

I would like to do a For loop with a jump 2*Pi instead of 1. For[j = 0, j <= nmax, (incr = 2 Pi), ...] Actually what I want to do is ...
0
votes
3answers
218 views

How to evaluate all the essentially distinct polynomials in 4 variables over $F_2$ on points of $F_2 ^ 4$

I am a beginner with Mathematica. For my research purpose I would like to get a list of all the polynomials in $F_2[x,y,z,w]$ and for each polynomial I would like to know the result that it gives then ...
7
votes
1answer
452 views

How can I get Mathematica to recognize the documentation for a newly installed package?

To install a new package on one's machine, one first downloads and unpacks the package into the $BaseDirectory/Applications directory. The tutorial Installing ...
0
votes
1answer
78 views

Error with minimization of NProbability

I'm trying to solve the following problem: ...
7
votes
1answer
499 views

Mathematica memory management for large arrays

I have come across a weird phenomenon in Mathematica when dealing with large arrays. When generating a list with all the possible subsets of three elements of another list (thus having elements which ...

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