1
vote
1answer
290 views

Need help with solving a second order differential equation

I need help with solving this differential equation. ...
0
votes
1answer
120 views

Maximization of a function within a unit square [closed]

I work in a unit square. I have some conditions under which areas within the unit square are defined. Say for simplicity that there are two conditions which define two areas. For example, if y > 1/2 ...
3
votes
1answer
63 views

Properly applying BandstopFilter

In the documentation about BandstopFilter it says that the cutoff-frequencies w1 and w2 in ...
0
votes
1answer
57 views

Specifying Table/grid dimensions in version 7

The result of my calculations is quite large list (nested list to be precise). I would like to improve its visualization, to make it more legible, by setting the number of columns to let's say 5. ...
0
votes
0answers
84 views

How to increase range in Plot without exceeding maximum bounds?

Does there exist some way to increase the plot range of following plot from 10^7 to new value 10^16? It exceeds its maximum ...
3
votes
1answer
155 views

Dynamic generation of Buttons

The Project I am trying to dynamically turn on/off the display of data for a circos-esque plot that I generated. The Code I have data stored in mfData and a ...
0
votes
0answers
197 views

Using Mathematica to Solve for Electric Field from finite cylinder

For a cylinder that is of length L and radius s and possesses a charge distribution of sigma across only the cylinder part and not the endcaps, I am trying to calculate the Electric-field. The ...
0
votes
2answers
164 views

How can I improve Do loop?

I have very large input of time series data (over 30000 observations) that look like as follows: ...
4
votes
1answer
576 views

Mathematica EPS graphics and psfrag in $\LaTeX$

I used to to use MathPSFrag in Mathematica to export graphics to EPS for inclusion in $\LaTeX$ files. However, with recent versions of Mathematica this does not seem to work very well anymore, see ...
1
vote
1answer
131 views

Solve equations for all values of variables, rejecting certain types of solution

I have an expression, expr, containing 3 variables, 4 coefficients and 2 non-zero generic constants. I want to solve for the 4 coefficients such that the equation ...
6
votes
6answers
546 views

Can someone help me solve this x*y*z=180

I have one question I've been trying for a while but I can't get the result for my equation.. So I've been trying hard but I can calculate only by hand but the problem is that I am afraid to miss any ...
0
votes
1answer
147 views

Why Eigenvalues thinks matrices are non-numerical

I use Mathematica version 9.0.1. ...
1
vote
2answers
169 views

Discretizing data using quantiles in Mathematica

I am trying to discretize a long array of real numbers into a uniformly distributed integer array. To do this I am identifying the quantile where each real value sits and writing it out to the output ...
1
vote
0answers
18 views

OpenCLLink specify grid size when calling function

The Mathematica documentation (section "Details": https://reference.wolfram.com/mathematica/OpenCLLink/ref/OpenCLFunction.html) states that: On launch, if the number of threads is not specified ...
3
votes
1answer
149 views

Problem with limit that requires L'Hôpital's rule to compute

Consider the following limit. Limit[(a - Sqrt[a^2 + x])/(a^2 - a*Sqrt[a^2 - x]), x -> 0, Assumptions -> {a > 0}] Mathematica 9.0.1.0 gives ...
5
votes
2answers
461 views

Filling between two spheres in SphericalPlot3D

Manipulate[ SphericalPlot3D[{1, 2 - n}, {θ, 0, Pi}, {ϕ, 0, 1.5 Pi}, Mesh -> None, PlotPoints -> 15, PlotRange -> {-2.2, 2.2}], {n, 0, 1}] I cant' ...
1
vote
2answers
306 views

Converting expression into string without evaluating it

How can one convert a Mathematica expression into a string without the expression being evaluated first? I tried using Hold, but it returns ...
1
vote
1answer
185 views

Is it possible to give the closed-form of the stiffness matrix of triangular prism element?

Suppose the vertices of triangular prism are 1, 2, 3 (bottom triangle), 4, 5, 6 (top triangle), the coordinates of the vertices are $$ (x_i, y_i, z_i), i=1,2,3,4,5,6. $$ We can write the stiffness ...
4
votes
1answer
101 views

TimeConstrained for parallel computations

The Mathematica manual states TimeConstrained takes account only of CPU time spent inside the main Mathematica kernel process; it does not include additional ...
5
votes
0answers
121 views

Output most efficient Fortran code by mathematica

I am trying to output most efficient Fortran code by mathematica 9.0 with the method Simon provided: How can I get Mathematica to produce better Fortran code? The expressions is as follows: ...
5
votes
3answers
2k views

Labeling points on a graph with their coordinates in parentheses

I need to create some graphs in Mathematica with a bunch of labels, such as axes labels, graph labels, etc. In particular, there must be some points that must be labeled with their coordinates. Thanks ...
0
votes
0answers
44 views

How to generate closed-form stiff matrix of triangular prism element by mathematica [duplicate]

We can generate closed-form stiff matrix of tetrahedron by mathematica: http://library.wolfram.com/infocenter/Articles/3233/ Can we also generate closed-form stiff matrix of triangular prism element ...
2
votes
1answer
232 views

Making a rectangular label for RegionPlot

I have a plot that includes a Region Plot. I want to make a rectangle with the same shading as in the region plot to show as a legend. The dumb way I can think off ...
1
vote
1answer
247 views

Latest Mathematica 9.0 can't use Format.m to generate optimized Fortran code [closed]

Before updating to Mathematica 9.0, I have successfully generated beautiful Fortran code using Mark Sofroniou's Format.m package, which is posted on MathSource. ...
6
votes
2answers
203 views

Evaluation in lambda function

If I have a function, that returns a function, for example: f[a_] := a^2 * # & then f[3] == 3^2 # & Is there a way ...
3
votes
0answers
270 views

How to determine BLAS/LAPACK implementation used internally for numerical matrix operations?

Is there a command which reveals which implementation of BLAS and LAPACK are used in Mathematica's matrix operations such as Eigensystem? I asked a related question ...
1
vote
0answers
58 views

Changing package content in batch

I would like to know if it's safe to do batch operations in a list of package files, applying a function like this: ...
0
votes
0answers
46 views

Set form of all output to InputForm

I try to interact with mathematica using MathLink for symbolic computations. By default it returns strings such as 2\012-1 + E\012-------\012 3\012 E if the ...
3
votes
2answers
139 views

Unset while running recursion

I am trying to run a recursive definition while at the same time clearing previously found values, so my memory is not completely consumed. I found this: How to clear parts of a memoized function? ...
0
votes
0answers
29 views

How to pass rules to packages [duplicate]

EDIT: After helpful comment from @Mr.Wizard I added the working implementation below for future reference. I wrote a module that does something with variables provided in form of a rule. It works ...
9
votes
4answers
591 views

Find positions of items in a list based on neighbours

How can I select items from a list where the selection criterion depends on the neighbouring items? For example select all indices where a change has occurred with respect to the previous element in ...
1
vote
1answer
153 views

How to define a summation with function calling itself?

I am new to Mathematica. I want to do this f(x)=summation f(t), summation is over t, where 1<=t<=x-1 and mod(x+1,t+1)=1, i.e. when x+1 is divided by t+1, remainder is 1 and f(1)=1. Should i use ...
2
votes
3answers
144 views

Applying Labeled Option to Multiple Options

First post. Hope it's not ignorant. I am trying to label several data points so I can label them properly on a ListLinePlot. I know I can label plots if I am ...
2
votes
1answer
275 views

Typesetting - entering derivative in traditional form

I am trying to work out how I enter a differential in standard notation? I am familiar with using D, but everything I have tried to enter a differential has failed. ...
1
vote
1answer
73 views

Reducing a multi-variate polynomial to have terms upto certain degree

I have a polynomial in x and y. I want to keep all the terms with (combined) degree 4. Any pointers will be appreciated. Simple tricks for doing the same with univariate polynomial don't seem to work. ...
7
votes
2answers
231 views

Analysis of many similar x-ray Images

From a 3d x-ray scan, I have many similar slices to analyze. Is there a way to determine the position of the three rectangles and the inner circle?
1
vote
1answer
230 views

Numerical saddle point problem of a function of many variables

I want to find the following saddle point of the function of 10 variables: . I am not able to find the stationary points by setting the first derivatives to 0, so I need do optimize the function ...
10
votes
2answers
343 views

How to take derivative of parameterized coordinate?

Suppose I have a vector in $\mathbb{R}^n$ but $n$ is not known in advance. I want to be able to write functions which operate on the components of that vector, and then I'd like to be able to take ...
4
votes
2answers
163 views

Capturing an F1

I teach an Intro to Mathematica course, and one of the things I try to reinforce early on is just how helpful Mathematica's help is. In the very first lab for the course, I even give the students a ...
2
votes
1answer
81 views

JLink function not producing result

I have a simple JLink function as follows: ...
1
vote
1answer
84 views

Editing the Virtual Book?

It's my understanding that the Virtual Book (of mathematica 9) is in notebook (.nb) format. It appears to be a very polished style of documentation which I want to reuse (parts) of it to create my own ...
0
votes
0answers
43 views

Using an Interpolating Function as a probability density function [duplicate]

I have seen a couple of similar questions but have not been able to figure out a solution for my particular problem. I have a probability density function of two variables ...
1
vote
2answers
167 views

How to make a single-variable out of a NDSolve solution?

So I've got this line that contains the solution of a partial, non-extraordinary differential equation (because Mathematica doesn't handle extraordinary partial differential equations): ...
0
votes
0answers
24 views

Create a (maybe nested) list of nminimize solutions in a loop [duplicate]

I'm a total newbie in mathematica, so need some help. I understand that my question is about basics, but i couldn't find the answer in docs, google and here. Here is what i'm trying to do. ...
2
votes
0answers
63 views

Autoupdate Section Numbers? - Technical Document Authoring with Mathematica

Technical document authoring systems are structured ways to create, manage, and update documentation for various mediums such as print, pdf, web, etc. Take a look at this technical document ported to ...
4
votes
2answers
274 views

Detecting changes of variables' values

Is it possible to detect (and create a trigger for) an event when any of the variables defined in the notebook changes its value (for any reason)? I need to know which variable got changed and what ...
5
votes
2answers
303 views

How to create this list more elegantly

There is list containing some $(i,j)$ values of indices. Now i want to create a matrix of dimension n $\times$ m whose entries are 1 for the indices corresponding to the given list otherwise its ...
0
votes
2answers
107 views

Coloring selected elements of a list created with Table [duplicate]

I have a function that returns a list of 100+ elements, using Table[]. For simplification, let's assume that it's just ...
6
votes
4answers
481 views

How to find an approximate solution in a region when Solve or NSolve does not work?

Consider the relation x/Tan[Pi x] == y/Tan[Pi y] Solve or NSolve can't give a solution ...

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