7
votes
1answer
200 views

What is the purpose of Dump contexts?

Motivation I've been trolling through some internal code, trying to glean design practices WRI developers employ when extending Mathematica using top-level code. During my ...
0
votes
1answer
510 views

Degree Symbol missing in PolarPlot when exported to PDF

I am trying to produce a polar plot. The axis should be in degrees. While no error occurs, the pdf export isn't working properly. Instead of the degree symbol I get ...
2
votes
0answers
201 views

Changing scroll rate for page down key?

I have a presentation remote that allows me to advance Mathematica slides when in the SlideShow environment. The control sends a page down key. Some of my slides extend below the screen window, and ...
4
votes
4answers
622 views

How to define and use a linear function

I have the following equation $T = -800n + 12000$. I know that this is a linear function and that the two points $(0, 12000)$ and $(15,0)$ lie on the line. When I have 2 other values of n between 0 ...
2
votes
4answers
280 views
7
votes
1answer
792 views

Import file from FTP site

I would like to Import files from an FTP site. The code below works on a test site: file = Import["ftp://test:test@ftp.secureftp-test.com/pigs.xml"]; But when I ...
6
votes
2answers
357 views

3D Plot: Number of Roots in x of a polynomial in x, a, b and c

I have a polynomial in four variables x,a,b and c. The number of roots of the polynomial in x depends of the choice of a, b and c. I would like to have a 3D-Plot with a, b and c on the axes, while the ...
4
votes
2answers
4k views

How do I plot $x^2+y^2=1$ in 3D?

How would I plot $x^2+y^2=1$ in 3D (it would form a cylinder)? Since there is no $z$ in the equation, I can't solve for it and use Plot3D. Or can I just put the ...
7
votes
1answer
269 views

How to make InputTable

There is InputField in mma but how to make InputTable? In MathCAD it`s possible to insert Excel spreadsheet with input and output variables.Input variables I use for filling of header row and column ...
15
votes
4answers
546 views

Accessing Reduce from DSolve

When solving transcendental equations, Solve frequently warns us that inverse functions are being used so that some solutions may not be found. We also see that ...
3
votes
2answers
278 views

Find all points that have the same minimum? [duplicate]

Possible Duplicate: How to find all the local minima/maxima in a range Sin[x] have two points ($3\pi/2,7\pi/2$) where the same minimum ($-1$) is achieved ...
4
votes
1answer
190 views

How to make a notebook that will be window maximized when open?

I use CreateDocument[cells, opts] to create a notebook. When the notebook is open, it has a small default windows size and I need to manually maximize it every ...
7
votes
0answers
249 views

Using Compile to speed up Function with PermutationProduct

I have the following fairly simple routine dot involving PermutationProduct that I wish to speed up using ...
10
votes
2answers
234 views
11
votes
4answers
560 views

How to make a Line[] with no end?

I'm trying to do this: In this graph, the secant points are aproximated in order to become the tangent, it seems I need some kind of function which plots a line based on two points and it's points ...
3
votes
2answers
383 views

Representation of negative exponents [duplicate]

Possible Duplicate: Way to improve “show me this decimal number to M places, don't use scientific notation”? How can I expand e.g. number 1.*10^-8 so that there would be no ...
-2
votes
1answer
314 views

Perimeter and area are positive integers

In Geometry 3D, How can I find the vertices with integer coordinates of a triangle whose perimeter and area are positive integers with Mathematica? Suppose its vertices $(x,y,z)$ has coordinates ...
10
votes
3answers
539 views
3
votes
2answers
671 views

Is there a way to get user input when running a script on a Linux terminal?

I have access to a node of a Linux cluster, on which Mathematica is installed. However, I do not have access to a Linux GUI. Typically I write and test Mathematica scripts on my Windows personal ...
8
votes
2answers
446 views

Generating a position lookup function for an arbitrary list of integers

In my code, I generate a list of integers called numlist. Here is an example numlist: ...
36
votes
6answers
2k views

Find zero crossing in a list

I'm looking for a function that finds the index of the zero-crossing points of a list. Before I go making my own subroutine to do this, I was wondering if anyone knows of any built-in Mathematica ...
2
votes
2answers
186 views

Import[] bug (video)?

I have the following code: frames = Import["myvideo.avi",{"Frames",{50,60,70}}]; This imports frames 1,2, and 3 of the video, not 50,60 and 70. It imports the ...
1
vote
1answer
232 views

Not able to load the package in CDF

I am facing a problem in loading the package. My code is working in Mathematica but after deploying it into CDF, it is unable to ...
2
votes
1answer
173 views

Controlling CDF window size

I want to ask how can I control the CDF WindowSize in such a way that the end user can minimise its size upto some extent only. ...
4
votes
3answers
193 views

Is it possible to replicate the “magic” of OptionPatterns[] with DynamicModule's local variables?

Creating richer interactive interfaces that are generated by a DynamicModule invariably requires more complex data structures and in particular, a larger argument ...
8
votes
1answer
276 views

Confused by (apparent) inconsistent precision

$$ e^{\pi \sqrt{163}} \approx 262537412640768743.99999999999925 $$ E^(Pi Sqrt[163.0]) N[E^(Pi Sqrt[163.0]), 35] NumberForm[E^(Pi Sqrt[163.]), 35] returns ...
2
votes
1answer
80 views

`Trigger` autorunning when not supposed to

Recently I was trying to make something where one could vary the parameters and press play to see how the animation changed. However, when I tried running the code it would just start automatically. ...
19
votes
4answers
806 views

Sort strings by natural ordering

Is there an easy way to sort strings according to their natural ordering? For example a list of file names ...
1
vote
0answers
173 views

How to move differentation before the integral?

I have quite a lot expressions that need to be integrated after switching the integral sign with differentation operator. The additional problem is that the bounds are dependent to one of the ...
2
votes
3answers
901 views

Finding eigenvalues of a $1500\times1500$ matrix

I need to find the eigenvalues of a $1500\times1500$ real symmetric matrix given by $A_{i,i+1}= A_{i+1,i}=-1$ and also $A_{1,N=1500}=-1$ (this is because of a periodic boundary condition used) and all ...
2
votes
1answer
114 views

How to prevent substitution?

I have a function: $\bar{u}:=u[t,x,y,z]$ (1) How do I prevent it from expanding and substituting in instructions like those following: $\partial _t {\bar u}$ (2) Thanks in advance EDIT: ...
13
votes
5answers
758 views

How are parameters evaluated for a Plot in Manipulate

I am trying to get my head around how Manipulate evaluates functions in a Plot. I have read the introduction to Manipulate, and introduction to Dynamic, but I still ...
1
vote
2answers
380 views

Piecewise function with a function as argument

I want to define a piecewise function, which has two arguments, one of which is a function of the other's piecewise argument. I am giving an example ...
1
vote
2answers
147 views

How can define a set of nested parameters

I would like to know how I to define a function with a nested set of parameters (or whatever you would like to call it). For example, how would I get the following function ...
4
votes
3answers
3k views

How can I plot the complex graph of $x^x$ in Mathematica?

For example, this Wolfram Alpha query shows this graph: But it does not show the code for plotting it in Mathematica. Plot[x^x, {x, -1, 1}] only plots the real ...
1
vote
1answer
485 views

Using previous two solutions as a start point in FindRoot

I need to solve a sequence of equations and I want the starting point of each new FindRoot to be the solution of the earlier FindRoot, increased or decreased by a a bit in the following way: Some ...
10
votes
0answers
156 views

Is there a convenient/automatic way of uploading a notebook into SE?

This post discusses how to streamline the other way - extracting code from a fragmented and longish SE answer but I imagine a two-way workflow like: Fashion an answer/question in an SE-templated ...
4
votes
2answers
457 views

How to fit one distribution to another?

I have a custom distribution created to model some experimental observations. While too complicated to include in this question, I can provide an example and some illustrations to convey a sense of ...
10
votes
2answers
3k views

How to get Matlab data imported with the same dimensions?

I have some Matlab image data with the following dimensions (output is from Matlab): >> size(im) ans = 86 86 3 45 The data imports just fine ...
2
votes
2answers
259 views

How to output an expression as a Dot[] product

How to force Mathematica to output an expression such as $a1u1+a2u2+a3u3$ as a Dot product like this one: ...
11
votes
5answers
671 views

How to plot rectangles aligned by their center?

Supose I have a rectangle which area is $x^2$. In some cases I may not know what is the size of each side, for $x=12,$ we have several possibilites: ...
7
votes
3answers
1k views

Finding the number of solutions to a diophantine equation

I want to count total number of the natural solutions (different from 0) of the equation $2x + 3y + z = 100$, but don't know how. How can I calculate it using Mathematica? I tried: ...
4
votes
4answers
2k views

How to convert equation to vector (matrix) form?

How can I convert expression a1*u1+a2*u2+a3*u3 to the vector form of dot product A.U, where ...
4
votes
2answers
532 views

Clustering a bivariate data set with Mathematica

I need to partition a bivariate data set into predetermined "n" clusters and, at the same time, to fix the centroid position of each cluster. Is the ...
6
votes
1answer
447 views

Count sublists which match pattern

I have a list which looks like this: data={{12,0},{0,0},{20,1},{0,0}, {0,-1}}. Now I would like to count the number of sublists which: have both slots zero the ...
5
votes
2answers
485 views

Rotated text in “plot” cannot be copied to MS Word

When I add some text to a simple plot with drawing tools, the text cannot be copied and pasted out with the graphic itself to Microsoft Word. Do you know how to copy the manually added text out to ...
3
votes
1answer
386 views

Problem in RegionPlot3D

I tried to plot the region bounded by the three planes. This is supposed to give me a pyramid type of shape (actually two, but I am just taking one of them). The code is given by ...
0
votes
1answer
608 views

Plot 3D vector that is a function of one variable

I have a function, r[t], which is a piecewise function that generates a 3D vector. It looks like this: ...
2
votes
1answer
508 views

Problems with FindMinimum for Constrained Optimization

I am trying to define a simple optimization problem, arising from the discretization of a simple Optimal Control problem. The problem that results is essentially linear, with bilinearities only ...
9
votes
2answers
179 views

How can I build an inline documentation utility?

I often have a large function to which I add inline comments, but then I can't see the forest for the trees. How can I make a tool that extracts the comments and tokens within them to generate an ...

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