# All Questions

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: ...
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: ...
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. ...
212 views

### Individual ColorFunction with RGBColor [duplicate]

I want to create a custom ColorFunction using RGBColor for my DensityPlot. A nice example is ...
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 ...
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 ...
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 ...
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 ...
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 ...
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 ...
218 views

### Throttle EventHandler KeyReleased

What might be the most elegant way to throttle the a,s functions triggered by an ...
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 ...
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, ...
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 ...
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 ...
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 ...
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 ...
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"?
117 views

### Converting code from Matlab to Mathematica [duplicate]

I have the following piece of code: ...
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 ...
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 ...
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 ...
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 $c_i$. ...
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)? ...
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. ...
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 ...
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 ...
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 ...
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: ...
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. ...
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 ...
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 ...
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 ...
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 ...
312 views

### Are there more pre-existing ColorFunction options?

Such as "DarkRainbow", "Rainbow", "BlueGreenYellow", and ...
252 views

### How can I plot the frequency of list items?

How can I plot the frequency of list items such as?: ...
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: ...
95 views

### TableHeadings align to the right

Is there away to get TableHeadings align to the Right instead of the default to the Left? ...
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 ...
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 ...
94 views

### Invisible plots

Im trying to plot the following. ...
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 ...
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: ...
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: ...
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 ...
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 ...
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 ...
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 ...