3
votes
1answer
129 views

How does Mathematica use system environment variables?

Is there a common way in which environment variables are accessed, stored, or used by the kernel? There are built-in functions for querying and setting vars in the system environment, but there are ...
0
votes
2answers
92 views

Open a .txt file in Mathematica [closed]

i have a .txt file written for Mathematica, but wenn I open it with Mathematica, there is just an unreadable text and no graphs and simulations like it should actually be, could you tell me how to ...
3
votes
3answers
137 views

Tooltip with ListLinePlot and interpolation

Is it possible to get the coordinates of any point on a graph using Tooltip, ListLinePlot and interpolation ? For example on this simple example ...
7
votes
5answers
926 views

Check if two lists are equal in any order

Suppose I have two lists, how can I efficiently check if the two lists are identical up to permutations of the elements? For example I would like the function to output: ...
1
vote
2answers
100 views

Change Temporary Directory

How to change the value of $TemporaryDirectory ? I need to change it because there is not enough space on the C drive and the calculation seems to stop after a while !
3
votes
2answers
198 views

Equation of a transformed (roatted) ellipsoid

Given an ellipsoid with semi-axis {a,b,c} and cantered at {a,0,0}, how do I use ...
2
votes
2answers
125 views

Matching a case when one element in a pair is Null

I've got a dataset of laitutdes and longitudes. Unfortunately, some of the dataset was from when a time when lat/longs weren't constantly recorded. So I need to remove the invalid data before working ...
0
votes
2answers
481 views

Problem in downloading “ToMatLab” package [duplicate]

Iam trying to download "ToMatLab" Package from http://library.wolfram.com/infocenter/MathSource/577/ but it is showing me an error message by showing a big question mark and "File could not be ...
0
votes
2answers
70 views

Restrict plot of object to be below a given plane in a ContourPlot3D

In a ContourPlot3D, I only want to part of the plot. Such as the part of a cylinder that lies beneath a plane. ...
7
votes
0answers
99 views

ParametricPlot MeshStyle bug in v10?

Update This bug is fixed in v10.0.2.0 Original Post The documentation gives the following code and says "Use a red mesh in the x direction and a blue mesh in the y direction:" ...
7
votes
1answer
207 views

Problem with Neumann condition in quarter disc

Bug persists through version 10.1 So I'm following the available examples in version 10 for FEM, The plane stress operator is shown as this ...
0
votes
1answer
91 views

Functions in functions

I have three functions f(x,y) , g(t) , and h(t) and somehow I have to find (d/dt)f(g(t),h(t)) where t = 0. How would I go about writing this in Mathematica? In this equation g(t) is taking place of x ...
2
votes
2answers
157 views

Solving 4 variable system of equations

Trying to solve a systems of equations. Here's the code: ...
2
votes
1answer
72 views

Problem with Style in a Plot

I would like to simply plot a density function $f_1$ and I would like to put a legend but I cannot do it as I wish. The problem is simple but I spent alot of time and couldnt solve it. I will be happy ...
1
vote
1answer
52 views

Automatically to add some points for a plot

Say I want to plot this Plot[x,Sin[x],{x,0,4 Pi}] And I want it to show 4 nicely spaced points, on the line. Is there an automatic way to do this? I was reading ...
2
votes
1answer
82 views

Struggling with FindFit

I'm trying to fit a sinusoidal wave to some numerical data. I can do it by hand using manipulate, so I know roughly the sort of parameter values that I should get back, but functions such as FindFit ...
3
votes
0answers
37 views

To UpSet or not to UpSet when using MakeBoxes

What is the difference between the following two: ...
2
votes
1answer
61 views

Truncating power series

I have the following typed up so as to truncate higher powers of $\tau$, ...
1
vote
1answer
165 views

Define a Recurrence Table involving other tables

I'm relatively new to using Mathematica. Previously I used Matlab, but lately I noticed that the numbers i got in both of them do not match (mostly it seems that Matlab lacks precision...). The ...
0
votes
1answer
132 views

Turning a 2D 3 body problem into 3D not so easy?

I have programmed a 3 body problem, that can in theory work for more than 3 bodies. I apologize in advance for the length of the code that I posted, I don't really know how much one would need to ...
5
votes
2answers
162 views

ListPlot inserts extra PlotMarkers and Mesh at crossing points

In the example below, ListPlot with PlotMarkers -> Automatic and a variant using ...
1
vote
2answers
50 views

How to fix the order in which text appears in an axis label (V7) [duplicate]

One of the AxesLabel is "$:\text{log}|\Phi8b(u)|\color{Red}{\text{Red}}$". Question: How to make it like: "$\color{Red}{\text{Red}}:\text{log}|\Phi8b(u)|$"?. My Mathematica commads: ...
10
votes
0answers
74 views

Is there a way to stop Export if the file size is too big?

I've got code that's exporting a file, but the file might be so big that it will take up too much space on the cluster I'm using and crash other users' processes. Is there anything like ...
2
votes
1answer
57 views

Identically styled cells from ToBoxes and Cell do not align

I'm trying to generate some worksheets using NotebookWrite so that I can control the page breaks, but have got stuck on the alignment as there appears to be a ...
8
votes
1answer
332 views

How do I generate cross sections of a 3D graphic?

I would like to approximate the volume of a bottle by summing up the volume of the individual disks. I have obtained code references from a demonstration. But how do I generate the cross sections? The ...
2
votes
1answer
120 views

Mean curvature of Sphere

I am trying to calculate mean curvature of a parametric surface(like sphere), and I wrote this code based on this discussion. Here is my code: ...
4
votes
2answers
276 views

Plane Geometry Diagrams With Labels

I can make some basic diagrams in Mathematica (stolen from their pages, for example see the below: LaminaData["FilledIsoscelesTriangle", "Diagram"] However, I'm ...
1
vote
1answer
78 views

How to calculate minimum positive solution of a equation?

Equations with triangular function usually have multiple solutions, like Solve[Sin[x] == 1/10, x] returns a solution like ...
1
vote
1answer
93 views

Problem using Compiled Function within NProbability

I've built a very simple function to estimate the probability for a Long Straddle (derivative strategy) to be positive at expiration. ...
0
votes
1answer
101 views

How can I stop the integration of NDSolve with a condition?

I try to solve a partial differential equation by NDSolve. At some point, I want to stop the integrating by a condition that compares the min value of the function ...
6
votes
2answers
205 views

Apply Trig Identity to Transform Sum of Sinusoids into Phase-Shifted Cosine Function

I'm trying to solve for the output of a simple RC low-pass filter, with Cos[w t] input. The convolution of the input with the RC transfer function gives me the right output, but I'd like to be able to ...
4
votes
0answers
231 views

What is the algorithm behind Mathematicas Reduce in this equation?

Mathematica can use Reduce to arrive at an answer in this equation ...
3
votes
3answers
238 views

Higher-order, nonlinear differential equation with Initial Values

I tried to solve for an non-Hookean spring's motion, but the output from Mathematica is weird. It seems that there is inverse functions involved. ...
6
votes
2answers
93 views

Mathematical operation on two lists by a “key” [duplicate]

I'm a complete newb here. Just looking for direction. I've got two lists like this... ...
3
votes
1answer
118 views

Image background subtraction using parallel computing

I am developing a program for pattern recognition. I want to use the parallel computing to get a real time application. I have two cameras where each one gives n frames/second. I need to process the ...
1
vote
1answer
176 views

Derivative of an expression containing a symbolic sum [duplicate]

Is there a general pattern for working with symbolic sums in Mathematica? For example here's a derivative I want to compute: ...
5
votes
2answers
226 views

Plotting two recursive functions

I'm trying to plot two recursive functions (p and θ) on a map. So far I have: ...
1
vote
1answer
92 views

Rationalize complex numbers

What is the best way to rationalize complex numbers, if not both the real and imaginary part are actually rational? According to the documentation, Rationalize ...
2
votes
1answer
270 views

Plotting on the Raspberry Pi

I just now powered on my new Raspberry Pi for the first time and tried the supplied Mathematica (Wolfram Language). One thing I tried was Plot[x, {x, 0, 1}] ...
4
votes
1answer
92 views

How to use Tandem Queueing Network Process?

Mathematica provides QueueingNetworkProcess and QueueingProcess. However, I can't seem to figure out how to create a tandem ...
0
votes
1answer
61 views

How to tell Eigensystem the type of the elements comprising a matrix I would like to diagonalize

How can I tell Eigensystem that a matrix $M$, which I would like to diagonalize, is a numerical matrix of complex numbers? My idea is that this information could ...
2
votes
0answers
57 views

Unexpected behavior from Indexed

I was going to include Indexed in this answer, thinking that it operated much as a List-only ...
2
votes
2answers
121 views

DSolve returning { } when given my ODE

Why does this code return {}? ...
1
vote
1answer
59 views

Summing subsets of array

I have an array farr, size Nx*Nx. I have a function frk that maps index {n,m} to an integer (approximately ...
0
votes
1answer
59 views

Loops for Unit Root Test

I want to compute some unit root tests on a data generating process. I already split the sample in 100 single samples, but how can I do a unit root test on all of them and store the results in another ...
2
votes
3answers
216 views

Extracting coefficients from a power series

I have a function defined explicitly as a power series: $$\sum_{n=0}^\infty{T_n}\frac{x^n}{n!}=\frac{\frac{x^3}{3!}}{e^x-1-x-\frac{x^2}{2!}}$$ and I would like to extract the coefficients $T_k$ as ...
3
votes
1answer
96 views

Draw function with different colors associated to a parameter

I want to generate a plot similar to this one, which allows for different colors when given different parameters : (This is the Moreau-Yosida regularization of the absolute value) the Moreau-Yosida ...
0
votes
1answer
52 views

Verticepair - route matrix

I have the following problem. I have two lists: list1 defines all possible commodities in a network g. E.g. Form vertex 1 to ...
7
votes
2answers
123 views

using memoization with conditional statement

I would like some advice about the use of memoization in conjunction with conditional statements. Let me try to explain my problem: I am constructing a function depending on a number of parameters. ...

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