3
votes
1answer
96 views

How do I test for the occurrence of an error message and act on it?

I want to see how well some curves fit a data set. If a curve doesn't fit after 100 iterations, I get the error cvmit. How do I test for and handle this error ...
3
votes
1answer
158 views

Combining the items with common available dates from two lists [duplicate]

I have two lists of data including dates such as data1 = {{{yy, mm, dd}, a}, ...} data2 = {{{yy, mm, dd}, A}, ...} There are some missing dates from each list, ...
2
votes
1answer
357 views

Finding a fixed vector which minimizes the pairwise distance between noisy elements in two unordered arrays

Let $A$ and $B$ be two sets of $d$-dimensional coordinates of comparible (though not necessarily equal length). For example, here we can set $d = 3$ and have normalized values like: ...
3
votes
2answers
224 views

WeatherData for the 15th day of each month

Suppose we have WeatherData["Helsinki", "MeanTemperature", {{2007, 1, 1}, {2012, 12, 31}, "Day"}] How we can have data just for 15th day of each month?
2
votes
1answer
197 views

Is it possible to use Find with wild cards?

When making global changes to code and variables Find is a great resource. Is there a way to use Find with wild cards to find and replace any non numerical elements or to find and replace only ...
3
votes
2answers
1k views

Sum over all permutations

I have n variables and a function that has all of them as variables. n-3 of them in terms of the entries of two lists. The possible entries in the lists $\alpha$ and $\beta$ range from {2,...n-2}. Now ...
2
votes
1answer
243 views

Optimal image quality using Rasterize Function

Based on previous posts about plotting two y axes on the same x axis, I wrote this function: ...
4
votes
2answers
701 views

How can I find the range of my function

I am trying to find the range of (3 Sin[x] - 3)/(2 Cos[x] + 10), I tried this, ...
3
votes
1answer
263 views

Using MatrixPlot, how can I dynamically zoom in and out with my mouse? [duplicate]

I have a MatrixPlot output which I would like to zoom around in, drawing boxes that define a zoom region with my mouse. These things are all fairly standard in Labview... surely Mathematica must have ...
25
votes
2answers
2k views

Complex valued 2+1D PDE Schrödinger equation, numerical method for `NDSolve`?

Based on the heat equation of the Mathematica Manual tutorial, I wrote the complex counterpart (Schrödinger) equation, for the free particle propagation of an initial wavepacket. ...
0
votes
1answer
544 views

Convert Mathematica formula to TeX (MathJax) with color

Case1: formula generated by functions. ...
10
votes
1answer
136 views

What are the scoping rules for function parameters shadowing System` symbols?

Here are some very contrived code snippets, highly unlikely to appear in real code, but still I am curious why they behave like this: ...
1
vote
0answers
117 views

Speeding up 2D histogram plotting (perhaps via ListDensityPlot)?

What would be the fastest way to take an array containing about $n=10^6$ to $10^7$ elements and plot a two-dimensional histogram with A x B bins? ListDensityPlot is taking upwards of half-an-hour. ...
1
vote
1answer
84 views
1
vote
1answer
185 views

CMYK colours in a graph template

Hi I'm trying to put together a graphing template. Unfortunately, my arrowheads are a different colour than my functions when the graph is exported to something like a PDF. Is there a way I can ...
9
votes
1answer
2k views

Minimization by Nelder-Mead

Finding a global minimum for this problem (non-linear optimization by the Nelder-Mead downhill simplex method) may not be possible, but by finding local minimum, I am expecting the value of the ...
1
vote
1answer
225 views

Bincounting a list

I'm a Mathematica novice here. I'm trying to execute the following code to add random 1's into a zero matrix, repeat this many times, and then bin/histogram the number of nearest neighbor 1s. Can ...
1
vote
1answer
137 views

Whats is the real difference between this two examples of using Dynamic with Grid

the question is relatively simple I think. This is the first example of the code which works: ...
4
votes
1answer
111 views

Exiting FindMinimum when a condition is met

I want to determine if a function f[x] can take negative values. f is expensive to compute and ...
1
vote
4answers
308 views

Calculating difference ratios (Δβ/Δρ) from a data set

I am little bit confused about how to calculate δβ/δρ value if I have set of values like this. I have the values of β and ρ like this. ...
1
vote
0answers
189 views

Problem with Integrate

...
4
votes
0answers
189 views

The guidelines for options or multiple arguments?

Where can I find some references concerning when to use options and when to use multiple arguments in designing and writing functions? Seems most built-in functions have arguments less than 3 and ...
0
votes
0answers
50 views

Ignoring Indeterminate Results [duplicate]

I am doing some program where I must calculate some numerical integral (the involved function is quite complicated to be solved analytically). The function to be integrated have some parameters which ...
5
votes
4answers
188 views

Make second argument same as first when only one argument passed to function [duplicate]

Clear[f] f[n_, k_: n] :={n, k} f[x] {x,n} Actually I would like to get: {x,x} The following is one wrong definition, I'm showing that I need the ...
0
votes
1answer
163 views

Is it possible to use some short form in Postfix

example 1 we can use Information , but can not use ? Sin // Information Sin // ? ...
18
votes
0answers
690 views

Nonlinear least squares on a GPU with Mathematica 9

Update: A Mathematica wrapper for (https://github.com/zitmen/cuLM) should allow for us to directly implement the Levenberg-Marquardt algorithm in CUDA for nonlinear least squares fitting. In a ...
0
votes
1answer
167 views

Plotting data with ListPlot where the coloration of the data depends on its position in an array?

Imagine I have some data in a list I'd like to plot using ListPlot in Mathematica 9, for example: ...
3
votes
0answers
82 views

Make all new cells have a specific style as a function of the Mathematica installation

I would like all new input and output cells, in fact all new cells including section headers and such, to have a specific stylistic property (...
-2
votes
1answer
562 views

Problem with plotting a function with NIntegrate

Why does the following Plot3D command never terminate? ...
4
votes
1answer
401 views

ListPlot coloring by density of points

I have a set of points on a circumference: points = Map[Normalize, RandomReal[{-1, 1}, {3000, 2}]] And I want to plot them and color the plot according to the ...
8
votes
2answers
382 views

Implementing a 100% Mathematica http server

I would like to dedicate a small machine to exclusively running a Mathematica kernel and use that kernel to read http requests arriving on port 80, treat them and send http responses back without any ...
13
votes
1answer
2k views

Is it possible to style multiple Plot or ListPlot curves using a color gradient?

I am using Mathematica 8. In Mathematica, there is a default PlotStyle coloring in Plot and ...
3
votes
1answer
164 views

HTML documentation build issue with Wolfram Workbench 2 and MMA 9

Using the Wolfram Workbench 2 (and Mathematica 9) to build HTML documentation for a package I am developing, I am ending up with HTML pages that contain a lot of text elements that look like this: ...
2
votes
2answers
240 views

Adding Dynamic functionality to a Graph

I would like to make the edges and vertices of a Graph interactive, a simple demonstration is to change their colors: ...
1
vote
1answer
142 views

Plotting three-dimensional plot with Interpolating functions

I want to plot my functions, but I can't seem to figure out what's going wrong. I want to be able to animate it as well. ...
6
votes
1answer
259 views

Generate regularly spaced points from the surface of simplexes

I need to generate regularly spaced samples (points) from the surface of unit simplexes with 2 or greater vertices or end points. I can generate random samples pretty straightforwardly: ...
7
votes
1answer
286 views

Series expansion for small ratio of variables

I have a messy expression of variables that I would like to simplify under the assumption that certain ratios of the variables are small. For example, consider $\sqrt{x+y}\;$ expanded for small ...
3
votes
1answer
532 views

How do I draw a credible velocity vs. time graph using Locators?

This is partly a math question, partly a Mathematica question. For educational purposes, I'm making a simple demonstration to create a velocity over time graph from six locators. On the basis of ...
1
vote
1answer
222 views

How can the evaluation queue be aborted?

While developing, I would sometimes like to stop evaluation of selected cells at a certain point. The following example nearly seems to work, but repeated runs of ...
6
votes
1answer
174 views

DynamicModule variables that retain values during code reloading

At times I'll find myself building a some interface component where I want to have some localized dynamic variables, and while testing I might realize that some bit of the code needs to change, which ...
12
votes
4answers
426 views

Cissoid of Diocles not smooth plotted by ContourPlot

Table[ContourPlot[y^2 (10-x)==x^3,{x,0,.1},{y,-.1,.1},PlotPoints->5],{k,1,150,10}] How to get the smooth graph? When ...
17
votes
2answers
3k views

Elegant way of obtaining the envelope of oscillating function [duplicate]

I am solving a differential equation numerically and the output is an oscillating function with the amplitude of the oscillation decaying in time. I would like to extract the power law governing this ...
5
votes
2answers
404 views

Adding noise to nonlinear control system using NDSolve

I have a nonlinear control system ...
20
votes
7answers
1k views

Elegant and fast way to join all string sequences

I want to do what title says: {"a","b",1,2,3,4,"a",2,2,2,"edg","?"} => {"ab",1,2,3,4,"a",2,2,2,"edg?"} in the most elegant way. For example one replacement rule for ...
3
votes
1answer
113 views

Why does saved graphic not look the same as graphic in notebook?

g1 = Plot[(x^2 - 4 x + 3)/(x + 1), {x, -5, 5}]; Rotate[g1, -90 Degree] After saving the output of the rotated graph, I still get the graph of ...
7
votes
1answer
927 views

Exporting a sequence of graphs as video efficiently

I have a sequence of graphs that are being created within Mathematica which I'm exporting to create an animated plot of the graph, as follows. ...
1
vote
2answers
838 views

Import Spreadsheet Data and DeleteCases of empty cells &/or choosing a Range to import

I am importing Excel spreadsheet data into Mathematica. Here is what the data looks like, notice the cell Q1 with "sdf": I import this data by specifying the Spreadsheet location, sheet name, top ...
6
votes
1answer
439 views

Creating a highly customized BarChart

I am trying to create a BarChart visualization for multi-step data filtering. Think of a traditional sales funnel: many leads, fewer prospects, few customers, very few return customers. The only ...
1
vote
1answer
149 views

Finding a mapping between elements in two lists that satisfy some criterion (such as being less than threshold Euclidean distance apart)?

I have two lists of $d$-dimensional coordinates, for example setting $d=3$ we might write: ...
4
votes
1answer
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.

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