3
votes
0answers
70 views

Antialiased text in manipulate constantly re-evaluated, ignores TrackedSymbols

I am trying to display antialiased text (using the ImportString[ExportString[]] method shown here) but inside a manipulate so that the text can be changed interactively. I have found a way to do this, ...
3
votes
0answers
56 views

What SampleRate and SampleDepth does Mathematica use on output?

The Play function will happily accept arbitrary values for its SampleDepth and SampleRate ...
3
votes
0answers
182 views

Understanding performance: graph connected components

I need to analyze directed graphs with 10M edges, 1M vertices, and 300K strongly connected components, so that the largest one contains 400K vertices. I read some explanations of Leonid Shifrin here, ...
3
votes
0answers
139 views

How to do Fast Fourier transform (FFT) for singular functions?

I want to do a 3-dimensional FFT on this function $\frac{\cos (x) \cos (y) \cos (z)-\sin (x) \sin (y) \sin (z)}{\left((1.0001+\sin (y)+\cos (z))^2+(0.0001+\cos (x)+\sin (z))^2+(0.0001+\sin (x)+\cos ...
3
votes
0answers
105 views

Authorizing use of proprietary code in the cloud?

As I continue to refine my working approach to deploying proprietary Mathematica code (see: Prevent package from being opened in a notebook interface and Run encoded package code through ...
3
votes
0answers
62 views

How to include automatic references to cells styled with DisplayFormulaNumbered

Under the Style menu, there is an entry called DisplayFormulaNumbered. It does exactly what it seems to suggest: it indexes the ...
3
votes
0answers
136 views

Why setting PlotPoints make my 3d contour plot broken?

I'm trying to make a iso surface plot from some data using ContourPlot3d. My data is a 3 dimension data with form like {{x,y,f[x,y]},...}. I first make this data ...
3
votes
0answers
58 views

What are good/best practices to take the Fourier transform of an InterpolatingFunction?

I have a function which I have obtained from numerical integration of a differential equation, and I would like to take its Fourier transform. What are good practices for doing this? To make things ...
3
votes
0answers
176 views

Module in numerical model for NonlinearModelFit is slow and leaks memory

I am trying to make a NonlinearModelFit where the model is the result of a numerical calculation. My code works, but it is very slow and also seems to have a memory ...
3
votes
0answers
139 views

Is it possible to model the piano key attack?

My purpose is to model the attack of a piano key. As the key is pressed a sound must be emitted. When the key is released the sound must stop with decreasing volume. I have a partial success when ...
3
votes
0answers
249 views

Function with a sharp resonance which Mathematica fails to integrate. Why?

I'm a new user of Mathematica and I'm trying to use it to calculate the collisional cross-section as a function of energy for a given potential and decay rate. I know that the resulting function ...
3
votes
0answers
109 views

Solving huge equations

I have this expression: $d=-\frac{\sqrt{\frac{780 (f+130) \left(5 d^2 (13 c+f+130)-5 d (c (f+1300)-325 (f+160))+125 \left(2 (2 c+725) f+5 f^2+104000\right)+13 d^3\right) \left(5 d^2 (52 c+17 ...
3
votes
0answers
89 views

Derivative of generating function (Example from documentation)

In the documentation for GeneratingFunction, the following example is given under Examples -> Properties & Relations -> Derivative: ...
3
votes
0answers
95 views

Getting Arg[z] to go from $0$ to $2\pi$

I'm defining branch cut functions, and I'm using $arg(z)$ as a building block. So I just spent an hour at the whiteboard assuming that $arg(z)$ goes from $0$ to $2\pi$, and then I implement the code, ...
3
votes
0answers
115 views

What can I do to improve the performance of my calculations?

I'm trying to express a simple probability problem in Mathematica, but am having trouble getting my calculations to execute at a reasonable speed. I have an object whose unknown location is modeled ...
3
votes
0answers
91 views

Compiling/calling Mathematica-generated .so from C

I'm trying to call a compiled function from a C program. I am generating the static object ...
3
votes
0answers
184 views

How to restrict the mouse cursor to stay within a box?

I'm trying to use Mathematica to write small games, and I find that it would help to restrict the player's mouse into the game window (just like other games do). Is there any way to achieve this? ...
3
votes
0answers
72 views

LibraryLink parallel performance

I'm trying to use a LibraryLink function in parallel. It is an embarrassingly parallel problem, so that no dependency between those parallel tasks. However I can only get the parallel efficiency about ...
3
votes
0answers
109 views

“Off-label use” of Mathematica functions for performance

Assisting an acquaintance with a simulation where a very large number of binomial probability calculations are required, I pointed them to a slightly obscure function to dramatically speed up their ...
3
votes
0answers
92 views

Deciding whether a semi-algebraic set is empty. Which command is best?

[Update] I was able to prove that the "larger" set $ 1\ge x \ge y,w \ge 0$ and $p(x,y,w)>0 $ is empty with another computer algebra system in my slow laptop in few minutes but in Mathematica even ...
3
votes
0answers
441 views

Problem inserting data into a mysql table with column names having a space

I have a mysql table whose column name has space. I tried inserting the data into this column. I got an error I tried a sample code, which tests accessing the columns with a space and that returns ...
3
votes
0answers
110 views

Using Graph to cull correlated lists

I have a set of lists that represent molecular descriptors. I need to identify which descriptors are highly correlated and eliminate the correlated pairs. I can represent the connectivity by ...
3
votes
0answers
296 views

A* algorithm for finding shortest path in a graph

FindShortestPath finds the shortest path between two vertices in an edge-weighted graph, allowing a choice between the Dijkstra and Bellman-Ford algorithms. In my (limited) understanding, both of ...
3
votes
0answers
136 views

Fourier transformation of HeavisideTheta functions

I want to find 2D-Fourier transformation of the function given below f = HeavisideTheta[y1]*HeavisideTheta[y2 - y1] For the purpose, I use built-in function in ...
3
votes
0answers
153 views

Using NVIDIA 3D Shutter Glasses with Mathematica

Mathematica has great capabilities to display 3D Graphics rendered to the 2D screen. This should make it perfectly suited to use the Graphics3D system together with an NVIDIA Graphics card, a 3D ...
3
votes
0answers
300 views

Masked Image Registration/Alignment/Correlation

I'm trying to register (align) two circular grayscale images using a boolean mask to prevent them simply being aligned on the fixed circular border. There are also small fixed circular regions in the ...
3
votes
0answers
146 views

Young Tableaux Miscellanea

I have a problem which is mostly neatly described by using Young Tableaux. Mathematica seems to have these Tableaux built in, except that the Tableaux function is ...
3
votes
0answers
113 views

Non-linear integral equation

I'm trying to solve with Mathematica an integral equation. I found this excellent answer (How to solve a non-linear integral equation?) solving with a collocation method a problem which can be ...
3
votes
0answers
152 views

Launching Remote Kernels takes a lot of time

I recently played around with establishing a remote kernel setup without using mathematica grid. To do this I use the LaunchKernels[] command and ...
3
votes
0answers
260 views

How to determine BLAS/LAPACK implementation used internally for numerical matrix operations?

Is there a command which reveals which implementation of BLAS and LAPACK are used in Mathematica's matrix operations such as Eigensystem? I asked a related question ...
3
votes
0answers
106 views

What is so special about variable s$?

I found a nice bug in Mathematica 9.0.1.0. Could anyone check to reproduce it? Create a file temp.txt with one line: ...
3
votes
0answers
109 views

Problem importing individual frames from QuickTime file

I am having difficulties with a code I am trying to run. Essentially I want to Read in a large .mov video file (60000+frames). ...
3
votes
0answers
67 views

Clean webMathematica Kernel

On my webMathematica server, certain input values are being saved between page loads on different computers. I assume this is because the kernel is not clearing the values after it finishes loading a ...
3
votes
0answers
109 views

random Poisson process over multiple variables (state vector) for chemical kinetics

Has anyone figured out how to coerce ContinuousMarkovProcess to work with a state vector, transition matrix, and rate (propensity) vector, and RandomFunction to return pairs of state vector and time, ...
3
votes
0answers
202 views

Sparse Principal Component Analysis

I'd like to run sparse PCA on some economic data. There appear to be several R functions available including elasticnet and PMA but I wanted to check if anyone had something coded up directly in MMA ...
3
votes
0answers
191 views

GUI Maker? Is there a perhaps drag and drop GUI maker for Mma?

IDE's like Borland, Eclipse, and others have ways of making GUI's. Drag and drop is usually the way of it. Then one puts the variables together and links up everything. Mma seems to handle (at least ...
3
votes
0answers
223 views

Mouse cursor disappears

After working on a notebook for a while sometimes my mouse cursor disappears. I can click on different cells and the text cursor will move accordingly but I just can't see the mouse cursor. Just now ...
3
votes
0answers
94 views

Tools for Stability/Automatic Error Analysis in Mathematica

I have a longer analytic expression in several variables containing special functions and others. Does Mathematica bring tools - or are there any packages - to examine the stability when I evaluate ...
3
votes
0answers
175 views

How copy a large cell into clipboard using `input text`?

This is a strange problem and everything I tried did not work. I have a very large single Manipulate cell (it is a demonstration stylesheet notebook, hence this cell have to be one), and I simply ...
3
votes
0answers
133 views

Do a gauge transformation for a Chern-Simons theory?

Suppose we have the following Lagrangian density: $$ L=\epsilon^{\mu\nu\rho}\big(\sum_a A^a_{\mu}(x) \partial_\nu A^a_{\rho}(x)-\sum_{a,b,c}\frac{1}{3} f^{bca} A^a_{\mu}(x) A^b_{\nu}(x) ...
3
votes
0answers
70 views

Understanding NDSolve::ndsz

I'm working on a largeish system of differential equations where I encounter the NDSolve::ndsz step size is effectively zero; singularity or stiff system suspected ...
3
votes
0answers
77 views

Efficient storage of Kronecker sum of circulant matrices+diagonal matrix

I have a square matrix of the form $$M=D+\overset{N}{\underset{n=1}\bigoplus}R_n,$$ where $R_n$ are circulant matrices, $D$ is a diagonal matrix and $\oplus$ is Kronecker sum. Its size is quite big, ...
3
votes
0answers
114 views

Where can I find the Distributions Palette?

I was watching the "Statistics: Modeling with Statistical Distribution" Training Course http://www.wolfram.com/training/videos/DAT016/ and in one of the slides, the following image showed up. Does ...
3
votes
0answers
72 views

How to combine DifferenceRoot objects for odd and even-indexed terms

I'm trying to analyze a certain infinite sequence $S$, indexed by positive integers starting from $1$. It can be split into two subsequences: $S^{odd}$ by removing all even-indexed elements and ...
3
votes
0answers
148 views

Problem with exporting a plot with a legend to PDF

I've found a simple example that illustrates my problem: ContourPlot[x^2 - 1 == y, {x, -1, 1}, {y, -1, 1}, PlotLegends -> "Expressions"] When I try to export ...
3
votes
0answers
252 views

Numerically solving a system of PDEs where one function is composed with the other

I'm trying to solve the following system using NDSolve: $$ \begin{align} u_t(x,t) &= u_{xx}(x,t) - v(x,t) \\ v_t(x,t) &= u(v(x,t),t) \end{align} $$ with ...
3
votes
0answers
206 views

Optimization with Matrix value constraint

I am trying to find the orientation and position of a polygon resting on a curved surface under gravity.The polygon MUST not be penetrated by any part of the surface below. Here is an example for a ...
3
votes
0answers
75 views

Copy string with markup so it looks good on input

How can I copy a string with a bunch of *Box expressions without it blowing up into the raw expression? ...
3
votes
0answers
119 views

What is the signature for a callback function for FinancialIndicators?

I'd like to write my own indicators to use with functions like TradingChart. From the context, it's clear that one needs to write a function whose parameters ...

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