# All Questions

205 views

### Dynamic and Refresh

If I am not mislead by my memory, in Mathematica 6 a function Refresh was introduced, having the options UpdateInterval and ...
291 views

### A smarter nested With?

I often find myself writing code that looks a bit like this: ...
355 views

### How can i construct a 3D surface pass through a curve defined by formula and some other controllable points?

For example, If a have a curve defined by x^2+y^2=1 and z=0, and some isolated points having z coordinates, Can I construct a 3D surface passed through? It's better if I can change the surface shape ...
631 views

### Collision detection algorithm (discrete) with sweep and prune algorithm

For a more complex collision detection approach, I need an efficient (aka fast) algorithm to prune the elements by using boundary boxes. A classical algorithm is the so called sweep and prune (SAP) ...
295 views

### How to use a compiled function in numerical optimization

I'm trying to wrap my head around function Compile. So, this is a spin-off question from: a previous question on using compile[] correctly. I have a function that ...
168 views

### DeleteMissing level spec confusion

Given: titanic = ExampleData[{"Dataset", "Titanic"}] Why does this correctly delete Missing[] elements: ...
368 views

### Hardware required to perform large symbolic calculations

I'm choosing components to set up a pc aimed to run large symbolic computations in Mathematica 9.0 under Windows 7 64 Bit Pro. I have a limited budget therefore I'm considering this system: Mother ...
223 views

### How to understand the process of ListCorrelate when it in two-dimensional condition?

Toady,I learn a function ListCorrelate,and I can understand process of execution his result in one-dimensional. However,the ...
169 views

### Changing mouse appearance at notebook level

Ideally, I'd like to change the mouse pointer appearance(s) at notebook level, from a styleseet. However, I'd be satisfied only by changing its color. This is the main issue keepeing me away from ...
470 views

### Parallel optimization of Markov Chain Monte Carlo

I'm trying to reduce the computation time of a MCMC simulation. Essentially I have a set of particles performing a random walk in a periodic random potential. The particles are independent and every ...
479 views

### Finding connected components in an array

I have an $w\times h$ array with non-negative integers. I wish to partition the set of coordinates $(c,r)$ with $1\leq c \leq w$ and $1\leq r \leq h$, in subsets, so that each subset corresponds to a ...
1k views

### Select a repeated element in a list

I want to select all elements that repeat 4 times in the list. I propose this code ...
323 views

### Cannot Get Numerical Results to Match

I try this numerical summation (in two parts) ...
681 views

### Fitting data to an ARProcess using FindProcessParameters

I have 50 data points that I would like to represent as an AR(4) process. I'd like to over-plot the behaivor of the estimated process model with that of the original (raw) data before I use the model ...
390 views

### Representative Smooth Kernel Distribution from Truncated Distribution

I am trying to produce a better distribution from a dataset that is bounded to be greater than 0. Here is an example distribution from the documentation that mimics the behavior of the actual dataset: ...
531 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 ...
2k views

### How to mark visible points on a Plot3D?

I'd like to illustrate a two-variable function discontinuous at zero. The function is $f(x,y)=xy/(x^2+y^2)$ unless $x=y=0$, in which case $f(0,0)=0$. I thought that I could draw a plot and then mark ...
4k views

### Mathematica function intersection points with 3D grid

I need to produce a 3-dimensional equispaced grid over a given function in a way, that I can calculate intersection points of the function with the grids edges. So my first question is how to produce ...
2k views

### Any way to prevent Mac firewall from asking to allow connections all the time?

Whenever I start Mathematica 8 on my Mac the built-in Mac OS firewall asks if I want to allow JLink to accept incoming connections. Then, during running, I'll get the same question about ...
2k views

### FeynArts not working properly

So I have installed all FeynArts folders (from 3.5 to 3.7) with FeynCalc 8.0.1., and none of it is working properly :\ First I load the path to specific FeynArts package (3.5 for instance), then, by: ...
2k views

### Is it possible to generate a Hasse Diagram for a defined relation?

I'm looking for a way to create a Hasse Diagram from a given partial order binary relation. The relation will be given explicitly, for example: ...
549 views

### How to overload System`StringJoin to automatically use ToString on arguments?

I am using an overloaded version of the StringJoin function since years now, without any problem, as I've invested a lot of time and effort earlier to make its ...
724 views

### Fit an image within a Rectangle [] in Graphics

Based on the following Code (yet the white text in the image is added with PPT), I would like to have an image fit within one of the rectangle. For Example the image from there : ...
771 views

### Replacing Tan[x] with Sin[x]/Cos[x]

Why doesn't this work? (1 - Tan[x])/(Sin[x] - Cos[x]) /. Tan[x] -> Sin[x]/Cos[x] I get back: ...
178 views

### Precompiling a Whittaker function

Is there a way to speed up the evaluation of special functions in Mathematica? I am particularly interested in the Whittaker W function. For instance, the following piece of code: ...
207 views

### Limit of partial sums involving inverse squares

Consider the finite sum rs[x_, n_] := x/n Sum[n^2/(i + (n - i) x)^2, {i, 1, n}] Is there a way to bring Mathematica to calculate the limit for ...
84 views

### Selecting the parallel kernels where tasks can be executed

When I use ParallelSubmit, is it possible to select on which kernel a task can possibly be executed? For example if have 3 parallel kernels, can I only use 2 of ...
585 views

301 views

### How can I Integrate large trigonometric expressions more efficiently?

I have a requirement to integrate some large symbolic expressions containing products of trigonometric functions. A single integration is averaging 7 minutes, and I have 2628 expressions to integrate, ...
545 views

### Why is there a huge performance gap using Map with more than 100 List entries

im using Map on a List like this: cube= {{1, 1, 1}, {1, 1, 2}, {1, 1, 3}, {1, 1, 4}, ... , {5, 5, 4}, {5, 5, 5}} Mapping the whole List with 125 entries takes ...
109 views

### Is it possible to Print into a collapsable CellGroup?

During rather long computation I have intermediate steps Printed with useful information which should be collected for possible use in future inside of the ...
1k views

### Asymmetric X and Y error bars on ListLogPlot

The wonderful error bar log plots package ErrorBarLogPlots from V6 no longer positions labels correctly (since ...
176 views

### Capturing an F1

I teach an Intro to Mathematica course, and one of the things I try to reinforce early on is just how helpful Mathematica's help is. In the very first lab for the course, I even give the students a ...
653 views

### Labelling objects in a picture with numbers

I need help processing a biology bacteria picture. I just started learning Mathematica and I hope you guys can use a simple method to help me solve the problem, please do not use super complicated ...
2k views

### Make a differentiable smooth sawtooth waveform

So, I am trying to understand the effect of sawtooth waveform on a mechanical system model. For example, a system of a plate and a box on it. And then we try to oscillate the plate. In order to do ...
617 views

### How to improve the solution of a double pendulum system

First, the code: ...
431 views

### ListPlot3D of a set of points in a non-convex region

I would like to plot a set of points in the same style as ListPlot3D does, but only in a non-convex region that I can specify (e.g. using a ...
91 views

I am using Mathematica 9 on Windows 8, and I regularly want to use cell styles such as Section, SubSection and so on. If I click the + button before creating a new ...
305 views

### Embedding StreamPlot in Graphics3D

I am trying to visualise the action of the infinitesimal generator of a Lie group on the solution of a 2-ODE system drawn in the 3D space (t,y1,y2): t is time and y1,y2 are the two dependent ...
303 views

### How to fold output cells by default?

In Mathematica the default behavior of output cells is to pop up after the kernel has processed the input cells and got a result. I know I could add ; in the end of ...
1k views

### How do you export the result of a RevolutionPlot3D to STL for printing?

How do you export the result of a RevolutionPlot3D to STL (STereoLithography) file format for printing? I am a tyro when it comes to 3D rendering and printing.
994 views

### What is the default ColorFunction for 3D plots?

This should be a really simple question, but it isn't in the documentation for some perverse reason. I like the default ColorFunction that Mathematica uses for ...
678 views

### Find the position of a string element, knowing only part of the string

I have a list, e.g.: list = {1, 2, 3, "Element 1", 4, 5, "Element 2", "Something else 1", "etcetera"} Now, I want all elements starting with ...
252 views

### Graph does not evaluate some options when not displayed

How can I force Graph to evaluate all its options without actually displaying the graph itself? Evaluating the following code ignores the ...
637 views

### Is Table the only functional way to construct nested loops in Mathematica?

Suppose you have a cubic box containing identical particles and you want to compute the distances between each particle and every other particle in the box without double-counting (i.e., if you've ...