10
votes
4answers
431 views

Rotated Rectangles

I would like to produce an image similar to the upper half of this graphics by Victor Vasarely. All I could produce so far is this dilettante image: ...
2
votes
2answers
524 views

Integration of piecewise function

I'm trying to understand why Mathematica is not evaluating a piecewise function, while it's able to evaluate each of the regions separately. This fails: ...
28
votes
2answers
3k views

How to build a bvh (a motion capture file format) player in Mathematica?

How to build a bvh player that can be used to visualize human motions in Mathematica? Any idea or sample code would be appreciated. ...
2
votes
2answers
212 views

Individual ColorFunction with RGBColor [duplicate]

I want to create a custom ColorFunction using RGBColor for my DensityPlot. A nice example is ...
6
votes
2answers
499 views

A problem about fixed point iteration theory

Description Recently, I have been learning a couse called "Numerical Analysis". The fixed point iteration theory was introducted to solve the ...
4
votes
0answers
57 views

Example in Help File does not evaluate as claimed

In the help file, under BellB, I read at "Properties and Relations": Sum can give results involving ...
3
votes
3answers
161 views

Composing function returning list and function taking multiple arguments

What is the easiest way to compose a function that returns a list of $n$ elements with a function that takes $n$ arguments. If I know this $n$ a priori, I can do something like ...
1
vote
1answer
125 views

Applying N to the roots found by Solve gives complex numbers when the roots are real [closed]

I have a function which is f(x) = x^3 - 5 x^2 - x + 1. When I solve for x to find the zeros ...
3
votes
1answer
175 views

Writing this loop in Mathematica

OK, so I've never had to write a line of Mathematica code (except for using it interactively as a calculator), but for this it looks like I have to. If someone could provide me with the code for the ...
2
votes
1answer
4k views

How do I change axes scale?

I am plotting f[x_] := 2*x + 1 Plot[f[x], {x, -10, 10}] BUT I want to scale my axes differently. By default it is 1:2 , meaning 1 unit on $y$ axis is equal to 2 ...
6
votes
1answer
218 views

Throttle EventHandler KeyReleased

What might be the most elegant way to throttle the a,s functions triggered by an ...
2
votes
0answers
124 views

Lat-lon contour plots using geographic projections

I need to create contour plots of (lat,lon) quantities projected on geographic regions using different projections. Usually considering the entire world or hemispheres. Coastlines need to be present ...
8
votes
3answers
561 views

Plotting triple data points while xy data are not regular

I plotted recently some figures in Matlab and their quality was not that satisfactory, so I come to Mathematica as my supervisor suggested. This is how such figure looks like in Matlab: . In Matlab, ...
7
votes
1answer
260 views

Fractal dimension of a large networked molecular system

I am trying to determine the fractal dimension of this complex biomolecule (figure attached). Any clues as to how this can be done. In trying to determine this quantity, I wonder how its ...
1
vote
0answers
74 views

Edge labels in GraphPlot3D from Adjacency Matrix

I am rendering a family of graphs via GraphPlot3D[AdjacencyMatrix] and I would also like to label the edges. I already use a vertex rendering function to color the ...
7
votes
2answers
353 views

Convert units to String

Is there a way to convert compound units to string? For example, I have "Newtons"/"Meters"^2, how to I convert it to "N/m^2"? I know If I do the following ...
8
votes
3answers
652 views

Biot-Savart Law/Magnetostatics Solution

I am working on solving the Biot-Savart Law equation for the magnetic field around a charged ring of uniform current density. The expression that Mathematica gives is rather nasty, as expected. Notice ...
3
votes
1answer
102 views

Is there a way to display units in short label?

For example, forQuantityUnit[Quantity[1, "Meters"]], is there a way to display the results as"m" instead of "Meters"?
0
votes
0answers
117 views

Converting code from Matlab to Mathematica [duplicate]

I have the following piece of code: ...
5
votes
1answer
151 views

Hyperbola plotting near real boundary

Plotted region above x-axis is jagged due to presence of Sqrt for y coordinate entailing delay in determining onset of real values. There is some improvement with higher number of points chosen,but ...
6
votes
2answers
471 views

Coordinate free differential forms package

I am looking for a package in Mathematica which can handle differential forms in a coordinate free manner. I am aware of several packages which do differential forms, but it seems that for all of them ...
1
vote
1answer
75 views

How do I know if NotebookLocate did not find the cell tag?

Is there a way to programmatically detect whether or not NotebookLocate[{"file", "cell tag"}] has found the cell? And then if not found, stay at current selection ...
9
votes
2answers
224 views

How to partition a list according to a value in the list

I have a list of the form $\{\{d_1,c_1\},\{d_2,c_2\},\ldots,\{d_n,c_n\}\}$. The values c_i take values between $1,\ldots,k$. I want to partition the data into $k$ lists according to the values $c_i$. ...
2
votes
1answer
174 views

Planar graph layout

Mathematica supplies planar graph layout, which draws a nice picture of a planar graph, but is there any way to get one's hands on the layout? For example, to find its faces (complementary regions)? ...
5
votes
3answers
106 views

GraphIntersection Problem

I Have a problem when plotting 2 functions. I want to find out where the two graphs intersect eachother. That said, I want the coordinates (x, y) of the point. ...
2
votes
2answers
208 views

Problem with NumberForm when exporting

I have a two-part question regarding NumberForm First question In my attempt at answering this i stumbled upon a strange behavior by NumberForm when the final result is exported. Lets say I ...
1
vote
0answers
70 views

Optimizing evaluation of expressions dependent on four variables and containing double summation

I would like to optimize my code which I use to evaluate expressions containing double summation. These expressions are dependent on 3 space variables ($r$, $\theta$, $\phi$) and time $t$ and consist ...
2
votes
1answer
186 views

Dynamic process on graph

I have a question, which I failed to find an answer to myself. I'm a casual user of Mathematica, but do have some knowledge about Dynamic module and other "Advanced" features. My problem is ...
3
votes
1answer
64 views

TransformedDistribution with respect to new variable

Given a custom pdf $f_x(x)$, I'm trying to find it's transformation $f_y(y)$ where $$y=x^2$$ and $$f_x(x)=30*x^2 (1 - x)^2, 0<x<1$$ I tried to using the following commands: ...
7
votes
5answers
2k views

Find function inverse

I'm trying to find the inverse of a function: (30*x^2 (1 - x)^2) (* where 0<x<1 *) I tried all the following options: 1. ...
2
votes
2answers
368 views

How to explain NDSolve that functions must be positive only?

I have a simple system of differential equations to solve but both functions should be positive: x[t] > 0 and y[t] > 0 for all t. I was not able to explain NDSolve this fact so it goes x[t] < 0 ...
3
votes
1answer
1k views

How to solve time dependent Optical Bloch Equations for a three level system?

I am trying to solve the optical block equations for three level system which are time dependent, which i generated using the "Atomic Density Matrix" package. When i use the command to solve this 9 ...
5
votes
2answers
174 views

Sorting out atom types in an XYZ file

I am trying to rewrite the output of "VertexCoordinates" such that instead of a hybrid list of atoms and coordinates that result from using the following input program, I want all coordinates of the ...
5
votes
4answers
318 views

Getting the number of frequency in a list

I want to know how to make a tally board in a specific data appear in a list. E.G. n ={1,2,1,4,3,1,4,5,3,2,4,5,6,3,4,2,2,5,2} and get ...
5
votes
1answer
312 views

Are there more pre-existing ColorFunction options?

Such as "DarkRainbow", "Rainbow", "BlueGreenYellow", and ...
5
votes
3answers
252 views

How can I plot the frequency of list items?

How can I plot the frequency of list items such as?: ...
4
votes
2answers
281 views

How to minimize the distance between two curves in 3D

I'm trying to find the shortest distance between r(t) and rm(t), at a certain time t. I could not get it using EuclideanDistance, any guess on how to do that? Here is what I have: ...
4
votes
2answers
95 views

TableHeadings align to the right

Is there away to get TableHeadings align to the Right instead of the default to the Left? ...
6
votes
4answers
174 views

Syntax for Table with a pure function

I have: g = #1^2 + a #2^3 / #1 & Now I wish to make a Table evaluating this from 1 ...
5
votes
2answers
166 views

Optimizing code containing an infinite sum

I have the following expression. It's based on the negative-log-likelihood of a Poisson-Gaussian noise model, i.e. a convolution of a Poisson & Normal distribution. The value $x_{i}$ is the ...
1
vote
1answer
94 views

Invisible plots

Im trying to plot the following. ...
6
votes
1answer
435 views

Creating a three dimensional fullerene molecule

How do I modify the following program to create a nice coloured molecular plot of C60 or fullerene as shown in the attached figure This figure was retrieved from ...
2
votes
3answers
247 views

Plot Epilog FindMaximum

So I have this: a=14; max = FindMaximum[x^3 - a x^2 - x + 1, {x, -2, 15}] (* {1.01781, {x -> -0.0355787}}*) And I plotted this: ...
25
votes
1answer
320 views

StringCases is Confused with Patterns in Version 10.0.1

Bug introduced in 10.0.1 and fixed in 10.0.2 I observed the following with StringCases when trying to use rules/patterns. Here is a screenshot of the behavior: ...
3
votes
1answer
161 views

Saving data from NonlinearModelFit

If you use NonlinearModelFit the results are put into some sort of output package. How do you save these packages so that you can go back to them later? My particular problem is that I generating ...
3
votes
3answers
185 views

Working with calculations that depend on the previous value in a list

I'm trying to make calculations on a list that depend on the previous value. In my case I'm doing event detection - detecting the point where a value rises above some threshold for the first time ...
6
votes
1answer
443 views

Pink Manipulates in stand-alone cdfs

Here is a simple example: Manipulate[Plot[Sin[2 Pi f t], {t, 0, 10}], {f, 0, 5}] This makes a plot with a sine wave of varying frequency determined by ...
4
votes
1answer
133 views

Export notebook as epub?

Is there a way (preferably easy!) to have Mathematica export a notebook or CDF as an epub document, to be read on an e-reader? It would certainy seem possible to export as HTML, and then use ...
6
votes
3answers
1k views

Assign output of solve to variables [duplicate]

I have this input: Solve[x^2 + 3 x + 2 == 0, x] which gives this output: {{x -> -2}, {x -> -1}} I want the first x ...
1
vote
0answers
175 views

Comparing two ways of fitting systems of ODEs to data

I'd like to ask you if you see any difference between the two following ways of estimating parameters. Given my system of ordinary differential equations that I want to use to find the values of all ...

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