# All Questions

18 views

### Find Vertex of Parabola

A Frisbee is thrown straight up in the air from a position 2 m above ground level. Because of the wind pattern, the height, h, in metres, after time t, in seconds, is given by the formula H = 2 + 6t – ...
14 views

### Calculate pixel intensity in two regions

I am just beginning to learn about image processing. I would like to know 1) how to show an original image with a visible mask of an arbitrary shape. And how to calculate the pixel intensities in the ...
13 views

### Function to calculate finite difference

I wrote a function to calculate multivariate finite difference of different orders ...
21 views

### Any approximations in EulerEquations?

I am using the Lagrangian method so I can numerically solve for the equations of motion for the double pendulum. It's been done by hand a million times and in every derivation, small angle ...
94 views

### Replace all integers by 1?

Let list1 be a list of variables of the form {c1 a, c2 b, ...} where $a,b,...\in\mathbb{C}$ and $c1,c2,...\in\mathbb{Z}$. I am ...
18 views

### There is an higher probability to win with 3 dices versus 2 or with 4 dices versus 3?

In Dice wars, you gain a territory rolling the dices you have in an adiacent territory (almost like Risk game). If I have more options to choose, there are more chances to win with 3 dices versus 2 ...
12 views

### How can I use parts of lists with Dynamic?

I'm a newbie - what am I doing wrong? I want to use parts of lists (vectors) in calculations but Mathematica will not evaluate anything that involves parts of lists that update dynamically. Is there a ...
25 views

### Breaking out of NDSolve

I am solving a coupled set of differential equations with NDSolve for 6 unknown functions of time. At a certain point in time, the system hits a singular point where the potential governing the ...
32 views

### Why Plot does not obey the AspectRatio specification?

I am plotting the density function of a beta distribution and I specify that aspect ratio should be one. I expect the x and y axes should have the same scale (unit length), but it turns out not. How ...
19 views

### Why First (or Last) and Take are distinct functions?

I think it would be better to make First take an optional second argument, so that First[list,n] is identical to ...
31 views

### Building bounded polygon around heatmap (or points)

I have a set of data for world marine piracy. I'd like to build polygons encircling areas of active piracy. So to start with I get piracy data and make a heatmap from it. ...
19 views

### SubsetQ returns unevaluated

I am using Mathematica 10.0.1.0, on Ubuntu 14.04.1. Executing SubsetQ[{1, 2, 3}, {1}] returns the same expression unevaluated: ...
10 views

### Again about a function defined by NIntegrate

I've looked on several similar questions but without success. Suppose I need to do the following (this is not a real problem, but only a scetch where an error appears): let (Kv)(x,s,t)=\int_s^t ...
37 views

### Visual representation of a Ranking over time (image provided)

[Disclaimer: I initially posted this question on stackOverflow 2 months ago and think it might be better suited for this forum (Original post: ...
217 views

### What quantity is this “length” called?

tmp = {x, y, z}^{1, 2, 3} Times @@ tmp Length[%] This gives a length of 3. But I was expecting 1. What is exactly this "length" of x*y^2*z^3 called? I would ...
80 views

### Matrices and Combination

When the positive integers 1 to 9, inclusive, are used exactly once as elements of a 3 x 3 matrix, what is the largest possible value of the determinant of the matrix?
40 views

### Custom list plot ticks

Not as exciting as the buttocks question, but ... For some list log plots, it is faster to calculate for certain log values. eg: ...
32 views

### Deferent results depending on the input form of the matrix [on hold]

Why is it so, N[Eigenvectors[{{1., 0.5, 4.}, {2., 1., 2.}, {0.25, 0.5, 1.}}]] returns: ...
36 views

### Combine Stereographic “Entity” Plot of Arctic Sea with Contour Plot

In the announcement of Mathematica 10 there were some very cool features for every geo-related researcher. Like this one what i'm trying to do is to overlay an ContourPlot onto this beautiful arctic ...
62 views

### Column Division

I'm new at Mathematica. I need to find all the reminders of a division between two integers - just like column division - and stop until I obtain a reminder equal to one of those already found. For ...
54 views

### List Manipulation Via Conditionals

I'm trying to convert one list to another by applying a condition on the list's elements. But I can't figure out how to do this in mathematica's language. Python example below ...
24 views

### Convert Dynamic to Manipulate

The following code is a modification of Wolfram code I found under ClickPane Help. I want to convert from Dynamic to Manipulate to make it easier for me to add various controls. I do want to keep the ...
47 views

### Blank sequences do not display anymore as continuous lines

BlankSequence[] and BlankNullSequence[] "suddenly" do not display anymore as "continuous lines" in my v.10.0.1 (OSX) (of course ...
68 views

### How to share LineLegend among sub-figures in GraphicsGrid?

Using GraphicsGrid, I have put two figures that share the same x-axis in a row. However, I failed to let them share a common ...
33 views

### Using N with Eigenvalues [on hold]

I'm calculating eigenvalues of matrices. The problem is that it works for some parameters and not for others. The output in my .dat-data has #1 [other stuff] #1^2 ...
44 views

### CDF Player - MMA9 - MMA10 oddities

I'm (slowly) building a WordPress site with some didactic simulation made with Mathematica. Users can run the simulations (on-line or off-line) with the free Wolfram CDF Player. One of the last ...
28 views

### The specified setting for the option FEFloatIterator cannot be used

I am currently trying to get a numerical simulation running where one variable is iterated over many orders of magnitude. As the calculation takes pretty long, I would like to display a ...
53 views

### How to prepare a Mma expression to insert it into Comsol?

Preamble Sometimes I have to solve nonlinear PDEs using Comsol. Often these equations I already have in Mma, written in a Mma notations. For this reason I would like to be able to transform them so ...
14k views

### How do I draw a pair of buttocks?

I'm trying to develop a function which 3D plot would have a buttocks like shape. Several days of searching the web and a dozen my of own attempts to solve the issue have brought nothing but two ...
96 views

### Finding the index of (x,y) pairs in a list

I have a large list of $(x,y)$ pairs, and I want to find the index of a particular pair in order to extract some data from another array. By way of an example, ...
54 views

### Plot multiple solutions [duplicate]

I want to plot multiple solutions of an equation, so that one can differ them in the plot. The given equation is e.g. ...
30 views

### Are there any build-in or third-party packages for general topology or algebraic topology in Mathematica?

I am learning general topology (wiki) and algebraic topology (wiki). Are there any build-in or third-party packages for general topology or algebraic topology in Mathematica? Through googling, ...
46 views

### How to Hold/Defer only one (only given) level?

Is it possible to Hold/Defer some of outer expressions, having evaluates inner ones? For example, I want to prepare a table of expression values, like this ...
91 views

### Physics Lab with mathematica [on hold]

Well, I am very new at Mathematica. I have some datas from my physics Laboratory. I used to use physplot, a simple program to plot data points,but now I want to use Mathematica to plot those points, ...
18 views

### choose a WSTP program to launch

When I run an external program(compiled by Visul C++ 2012 in windows 7) to use the wolframkernal by WTSP, for example:project1.exe -linkmode launch,it will open a dialog box named "choose a WSTP ...
59 views

### Turn a string into a list of strings [on hold]

Is there a way to turn a series of letters, say: "kspe" Into a list composed of strings (not variables) in the form of ...
33 views

### Composition of Multivariable function

I am trying to compose functions of xleft, maybe like xleft[xleft[f]] or even higher order. And here is my function: ...
49 views

### How to make Graphics3D with multiple lighting sources being rendered faster

I have a very "precise"(through setting "SpherePoints") Sphere illuminated by hundreds of random color lighting sources. The ...
160 views

### How can I import and split lines with ASCII separator?

This is my data file, each line was separated by SOH, maybe hex \x001, I've tried some options of ...
65 views

### How to turn an expression into a number

I am working with a function that computes the covariance between two variables. After computing this, I'd like to use Plot or Plot3D to see how this covariance depends on the parameters of the mean ...
49 views

### how to make interpolated data as a function?

For example, data1 = 0 1 1 2 3 3 5 2 6 2 9 4 11 5 13 6 14 7 16 8 data2 = 0 2 1 3 2 2 3 1 4 2 6 3 8 4 9 6 11 4 16 7 each data have different x-axis interval. so ...
52 views

### How do I use an offset with Parametric Plot?

This is a line of code from a Mathematica demonstration called "Coupler Curves of a Four-Bar Linkage". ...
41 views

### How to export a ParametricPlot3D as .stl for 3D printing

I am a attempting to render and export a model lorenz attractor to .stl using Mathematica, so that I may 3D print it! I was able to come across a notebook (from a deeper end of Mathematica than I swim ...
47 views

### Why Delete does not work?

I'm trying random thing in Mathematica just for learning and I can't solve this problem. I want to use the Detele function to delete some elements in a list but ...
39 views

### Parallelization and memoization? [duplicate]

I have an expensive function on discrete values, f[n_] := f[n] = n^2 (* Expensive calculation *) Since f[n] is an expensive ...
44 views

### Is the “Table” function limited in number of elements it can compute? [on hold]

i tried using "Table" to compute a list of 400,000 strings but the output takes forever to get. I have tried with smaller size of about 100 and i get results as fast as possible. But when the number ...
19 views

### Parsing RLink RObject for summary.aovlist

There's some slightly similar requests out there (e.g. Getting R textual output into Mathematica ) but I'm wondering if anyone has put together a more general purpose solution to parsing ...
33 views

### Plot function producing no graph [on hold]

I am trying to plot this probability distribution but nothing is showing up on the axis: ...