19
votes
2answers
532 views

Dynamically splitting Disks with Mouseover

I've recently stumbled across this site: Koalas to the Max, and the first thought that came to my mind was "I want to recreate this with Mathematica". As a first step I tried to create a ...
2
votes
1answer
209 views

Thickness option in FillingStyle

I have the following ListPlot: ...
9
votes
2answers
650 views

Usage of Assuming for Integration

For some reason, when I enter the following integration in Mathematica Assuming[{k ∈ Integers}, Integrate[ Exp[ I k t], {t, -π, π}]] the result turns out to be ...
1
vote
1answer
129 views

Creating an array eval [closed]

How can I create an one dimensional array (a vector) evaluating a function of two variables? I know how to do it with one variable: Array[f, n, {a, b}] generates a ...
14
votes
4answers
1k views

Find the minima and maxima of a list

I have a list, such as: ...
4
votes
1answer
129 views

How can I prevent a polynomial from being simplified?

I'm having a problem with polynomials. Let's say I have a polynomial "2x^2 - 5x + 6 - 3x^2" .. How can I check that this expression is not simplified ? Additionally, I would like to locate the ...
2
votes
1answer
415 views

How to export/import function values [duplicate]

I have a function with two variables: f[x_,y_]:=f[x,y] = ... I calculated some values (they are fractions like 435345345/3424242424) and would like to store the ...
3
votes
1answer
634 views

Extracting polygons from 3D contour plot surface

Edit: This question turned out to be two parts so I am going to make this question about only the first part a kguler provided an excellent answer. Here is a better representation. My actual data ...
15
votes
1answer
239 views

Multiple templates for a single user-defined function

How do I use the ::usage tag to allow the Mathematica v9 front end to know that there are multiple ways to call an overloaded function (a function that can have ...
7
votes
1answer
345 views

FullGraphics ticks problem

In the document of FullGraphics, it promise to produce the same graphic result as the input one: ...
6
votes
2answers
238 views

Fastest way to test if a numerical array has complex elements

I am looking for the fastest way to test whether an n-dimensional numerical (NumericQ) array (in the ArrayQ sense) is complex or ...
5
votes
1answer
238 views

Evaluation order control

This question is related to Evaluation order of Button[]'s action Concusion was, Button[]'s actions are evaluated in preemptive link so "the code that needs ...
1
vote
0answers
71 views

Defining a Function, := versus = [duplicate]

Consider: ...
9
votes
2answers
295 views

Speed up 4D matrix/array generation

I have to fill a 4D array, whose entries are $\mathrm{sinc}\left[j(a-b)^2+j(c-d)^2-\phi\right]$ for a fixed value of $\phi$ (normally -15) and a fixed value of $j$ (normally about 0.00005). The way ...
2
votes
2answers
513 views

3N-dimensional integral

I'm trying to compute a multidimensional integral with a variable number of dimensions. The integral is as follows: $$ \int d^{3N}\!p~e^{-\frac{\beta}{2m}\vec p^2}. $$ I have tried this ...
0
votes
1answer
115 views

Is RemoveSymbolize the reverse of Symbolize?

why cann't I use RemoveSymbolize[ParsedBoxWrapper[SubscriptBox["_", "_"]]] to remove all subscripts? Just like ...
4
votes
2answers
528 views

What function returns all possible permutations with repeating list elements? [closed]

Let's say I want to find a sample space of such experiment: There are three exits from the box: Left (L), right (R) and front (F). Three mice have been put in that box. Find the sample space of an ...
1
vote
1answer
404 views

Drawing a quadrilateral inscribed within a circle

I would like to draw a quadrilateral inscribed within a circle. How can I construct this figure, taking into account arbitrary (specified) side lengths, while still ensuring that the vertices of the ...
2
votes
1answer
171 views

How can I specify the exact colors two Polygons in plots combined with Show?

I made two Polygons with different colors. Their names are p1 and p2. ...
-5
votes
1answer
119 views

Help in coding of differential equations [closed]

I need some help with Mathematica. How can I do the following? Starting with f = y[0]^2 (y[0] is basically y with 0 subscript) ...
0
votes
1answer
222 views

Why does memory run out when adding same-sized matrices in a loop?

I have written a module that it generates a 101x101x51 zero matrix at first. At every iteration, it generates a list by funct1 and based on this list, if list is empty it gives the previous result. ...
21
votes
2answers
2k views

How to form a block-diagonal Matrix from a list of matrices?

like this: I know join[...] works, but it is a bit troublesome for multiple matrices.I tried DiagonalMatrix[...], but DiagonalMatrix can only form matrix from a list of elements.
0
votes
1answer
131 views

Saving/exporting results from FindInstance and similar functions

I am dealing with a problem that requires the use of both FindInstance and FindRoot nested in a non-trivial way. The result is dependent on some parameter value $t \in [0,1)$, therefore I use ...
14
votes
1answer
269 views

Is the sharing of variables in Module/Block within Compile documented behavior?

Today I noticed something, I think for the first time. When used inside Compile variable values within Module (and ...
7
votes
3answers
155 views

Given a list of lists, build a list in which lists with equal first and last elements are grouped together

I have a list of lists, and I'd like to build a new list, in which lists are in the same list if they have the same first and last element. Here's an example. Suppose I have ...
3
votes
1answer
103 views

Is it safe to assign a variable and function of the same name for different things?

I'm writing out a notebook that goes through the van der Waals Equation of State for gases, and I run into a situation where I want to assign (simplified) Tc[b_]:=5b, use that to solve for b in terms ...
4
votes
1answer
407 views

Details about Symbolize

When I'm using Symbolize function, there are some details that I'm not sure. For example: ...
7
votes
4answers
379 views

How to set Block local variables by code?

I need to create a user defined Block function where the Block variables values are defined by code. For example, imagine I have: ...
3
votes
1answer
286 views

(Centered) Automatic Numbering of Figures

I want to create a figure caption cell style that prefixes a centred figure caption with Figure X, where X is an incremental number I have seen two methods for automatically numbering figures: ...
0
votes
1answer
114 views

Where do those nulls come from? [closed]

I have seen discussions of unwanted nulls in the output in the context of building lists with conditions on the elements, but that is not involved here. I would like to know where the nulls come from ...
3
votes
1answer
100 views

Contexts after Cell Grouping

I'm trying to separate my document into cell groups, each with their own context (much like the style of code isolation described by the answer here: Localizing variables within a Manipulate), but the ...
0
votes
2answers
477 views

Is it possible to use WolframAlpha servers to evaluate equations in Mathematica v8.0.4?

Is it possible to use WolframAlpha computational power to evaluate equations in Mathematica version 8.0.4? The thing is, it takes ages for my computer to evaluate certain equations. It would be ...
10
votes
2answers
468 views

Dynamic graphics are less responsive inside a Manipulate

I have some code which displays a GraphPlot and allows the user to click on any vertex in the graph to display some information about that vertex in a popup window. ...
5
votes
4answers
263 views

Manipulate flickering and consuming lots of CPU

I am new to Mathematica and was experimenting with a simply problem of plotting a tangent to a curve and being able to move the point at which the tangent is drawn using ...
3
votes
3answers
233 views

How to transform and swap columns of this matrix in a simple way? Version 2

So, earlier today I asked the question How to transform this matrix & swap its columns in a simple way? and was given useful and elaborated answers. Now, I'm still not used to the "Array", ...
0
votes
2answers
555 views

How to get complement from two matrices?

This is a special case of my question How to do nor on matrices? ...
3
votes
4answers
341 views

How to transform this matrix & swap its columns in a simple way?

I would like to transform matrix $\mathbf A = \begin{pmatrix} a&b&i&j\\ c&d&k&l \\ e&f&m&n \\ g&h&o&p \end{pmatrix}$ into matrix $\mathbf B = ...
3
votes
1answer
154 views

How to make a simple tree yourself with defined distances for each generation?

I'm trying to make a function that generates a tree for spin spin analysis in spectroscopy. I though it would be pretty easy, but I'm totally stocked. The tree should look something like this: ...
0
votes
1answer
152 views

How to do nor on matrices?

Supose I have matrices a b and c like a = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}; b = {7, 8, 9}; c = {{1},{4},{7}}; I want to get ...
5
votes
2answers
427 views

How to declare a function of variable?

In my program, there are many functions relying on spatial coordinates: x, y, and z, which are also functions of time t, i.e., composite function. I need to differentiate some functions for example f: ...
3
votes
1answer
144 views

Creation of name.m Package

I have a structure of folders. Main Directory( has init.m, and name.m files) Subfolders under Main directory library ( has the packages, pacakge1.m, package2.m) Data (some xcel sheets and other ...
0
votes
1answer
2k views

Complex line integral

Can someone recommend an online article or introductory tutorial that will show me how to do real and complex line integrals using Mathematica?
7
votes
2answers
648 views

How to change an expression to Fortran90 form?

I have a large expression produced by Mathematica. To use this expression in my Fortran program I need to change it to a Fortran90 form. I am not satisfied with the ...
0
votes
0answers
97 views

DensityPlot on spherical surface? [duplicate]

I just checked this example Construct a Globe Showing All Weather Stations. It looks good, but I would like to add a density plot of the stations on the spherical surface. This can be done with the ...
7
votes
2answers
130 views

Method that can be used to collect the variables of a function

Suppose we have a function f[x, y, z] and we want to get all its variables Sequence[x,y,z], what method can we use then? The ...
12
votes
2answers
585 views

Simplify assumes Boolean 1 and 0 in logical expressions

Per this chat discussion and this previous question where I encountered the strange behaviour: ...
9
votes
2answers
1k views

Badly conditioned matrix (General::luc)

With some matrices I am receiving the following message ...
4
votes
1answer
371 views

iterating piecewise linear maps on [0,1]

I have been trying to make code work for iterating piecewise linear maps on the unit interval in Mathematica to compare with MATLAB and Maple. Tent and logistic maps are easy to implement but ...
4
votes
1answer
367 views

NDSolve problem with matrix valued function

I got a strange problem when using NDSolve to solve a matrix value function σ[t] = {{σx[t], σxy[t]}, {σyx[t], σy[t]}} when I ...
8
votes
3answers
301 views

Patternmatching sets

How to match set-patterns against sets? A set (in the mathematical sense) is a list of elements without repetition and order of elements does not matter. For example, we have a pattern set ...

15 30 50 per page