Questions on writing non-trivial programs in Mathematica. Do not use this tag for questions on plotting/graphics or for questions on doing mathematics with Mathematica, where the focus is more on the math than the program.

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3
votes
0answers
75 views

Programmatic immersion of 2D surfaces in 3D [closed]

Disclaimer: This may be an open problem, or one that is too large to be amenable to a solution on this site; I'm not sure. Question: I'm looking for a method to programmatically immerse certain ...
3
votes
0answers
107 views

What is recommended way to define my function option

In Mathematica 5.x days many packages used the following standard mechanism to read option values ...
3
votes
0answers
32 views

How to identify the program that is running my notebook or CDF file [duplicate]

Is there a way to programatically know which Wolfram product is evaluating a notebook or cdf file: Mathematica, CDF Player, or CDF Player Pro, Wolfram Cloud? I'm currently using $InstallationDirectory ...
3
votes
0answers
90 views

What am I missing in this highly oscillatory integral?

I want to numerically integrate this equation (in python without calling Mathematica): $\int_0^\infty {\rm d}k f(k) J_v(r k) J_n(s k)$ where $f(k)$ is a non-smooth function, $J_v$ are the Bessel ...
3
votes
0answers
264 views

Distance Time Warp (DTW) function implementation in mathematica

The DTW (Distance time warp) is given here http://en.wikipedia.org/wiki/Dynamic_time_warping There is an implementation of DTW in R as well as MATLAB. However i am unable to find something for DTW in ...
3
votes
0answers
72 views

Can BreadthFirstScan be modified?

I would like to obtain a "slick" implementation of A*-search algorithm on Graph objects, using the built-in BreadthFirstScan (if that is possible at all). I noticed that BreadthFirstScan is static in ...
3
votes
0answers
547 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
247 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
48 views

Is it possible to enclose code into collapsible/expandable regions? [duplicate]

In some programming languages (e.g. C#, Visual Basic) there are language constructs that have no effect on the execution of code whatsoever, but exist solely to allow grouping fragments of code into ...
3
votes
0answers
323 views

How to compute the Lovász number for the given graph in Mathematica?

Here is a graph whose adjacency matrix is ...
3
votes
0answers
59 views

How can I append Mathematica variables to an output file preserving both names and values? [duplicate]

I have a Mathematica program that calculates a series of large vectors that I need to save for future reference (in addition to some scalar values). I want to save all these to a file, tagged by their ...
3
votes
0answers
250 views

Malliavin Derivative with Mathematica is it possible?

Is it possible to define a Malliavin calculus with Mathematica 9? Consider a random variables on the Wiener-space $\Omega=\mathcal{C}([0,1])$ of the form $$F=F(\omega)=\displaystyle\int_{0}^{T}h_{t}...
3
votes
0answers
179 views

I am missing a function like HoldPattern

Temporary message: I am planning to edit this question, making the examples less confusing and by moving the things that are confusing to a separate question For any confusion about expressions that ...
2
votes
5answers
528 views

How to leave function unevaluated programmatically?

Is it possible to write a function in such manner, that it can be either evaluated or left unevaluated? This is a general question. Sample below is just a sample. No need to find solution for this ...
2
votes
2answers
1k views

optimization problem with NDSolve

I want to minimize the function fcc. When fcc is calculated for a specified point the answer is correct: ...
2
votes
4answers
618 views

Using the result of Solve in subsequent calculations

I'd like to know how to use the results of Solve in later calculations. Here's what I'm doing now: This is my expression ...
2
votes
1answer
170 views

Translate C++ in Mathematica 10.0.2 [closed]

By translating the following program written in C ++ ...
2
votes
1answer
133 views

Odd edge-case behavior of Block

In this example, Block is used to localize the variable cache as used in the function g when called from the function ...
2
votes
2answers
90 views

Double For loop problem [closed]

I am not really sure how to post my original data here, because the Tables I am using are rather big - too big to copy them here. I will try to describe what the problem is. I have three separated ...
2
votes
1answer
877 views

Using triangulation

I have been presented with 3 known points and the power densities at those points. I need to use those points to find the location of the actual antenna which is generating the signals. Power ...
2
votes
2answers
467 views

How can I find minimum and maximum of a region?

I have a regionplot like the following: ...
2
votes
3answers
191 views

Using Nest inside NestList

I need results like this: {Cos[Cos[x]], Sin[Cos[Cos[x]]],Cos[Cos[Sin[Cos[Cos[x]]]]], Sin[Cos[Cos[Sin[Cos[Cos[x]]]]]], ... } I've tried to use ...
2
votes
2answers
219 views

How to unprotect GeneratingFunction

I'm trying to add custom downvalues for GeneratingFunction, and to do so I thought I just had to Unprotect it. However, that ...
2
votes
3answers
206 views

How can I find the points of B Spline functions for a specific range?

Based on this question: I have a list of bspline functions (nearly 1000) provided by applying BSplineFunction to a list of points. I want to get the points each of ...
2
votes
5answers
165 views

GatherBy based on condition imposed on index variable

Excuse me. This might be user specific question but I need your help. I have an indexed data, where positive integers are used for indexing data. I am trying to group data putting condition on index ...
2
votes
3answers
195 views

How can I use NestWhileList instead of While in this case?

OK, the problem occurred when I challenged with Project Euler No. 10 The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million. My code is: ...
2
votes
2answers
228 views

How to replace data in a list (tree) in a functional Mathematica way?

I have list containing 2D points in various groupings, i.e. points, lists of points (figures), lists of lists of points (patterns) and finally a list of patterns. The list also contains other data, i....
2
votes
2answers
618 views

Mapping multiple functions

This question was part of a course on Mathematica written in 1998. Each of the functions f1, f2, and f3 defined below has a root near x=2. Map an anonymous function involving FindRoot[] onto ...
2
votes
3answers
295 views

How do I construct a pure function to extract data fields from records that are strings?

How can I get from data segment format to the final segment format with a pure function? The data fields are fixed length. There are no separators between the fields. a) list ...
2
votes
3answers
142 views

How to extract both first and last rows of each group from unbalanced panel data

This is a follow up question form my last question click here. I have unbalanced panel data such as : ...
2
votes
4answers
146 views

multiple sequential definitions, defining own set function

I want to define a function for doing multiple definitions, where I apply the same function f to all values, and definitions are done not at the same time but after ...
2
votes
2answers
4k views

Product of Fibonacci numbers using For/Do/While loops

I want to find the product of the first 20 Fibonacci numbers (the fibonorial). I want implementations using While, Do, and ...
2
votes
1answer
1k views

Optimizing a function involving NDSolve results in error messages

I want to minimize a function f with NMinimize but an error occurs that says: ...
2
votes
3answers
98 views

How to compare and remove x-coordinates (and the associated y-coordinates) that are less than previous x-coordinates?

I am using Mathematica version 9.0 and am trying to compare and remove x-coordinates, and the associated y-coordinate, that are less than previous x-coordinates. Below is an example using sample data. ...
2
votes
2answers
81 views

Sum broken into two sub-sums according to a condition on the terms

I have a sum in mind, but I want to break it into two sums and get a separate total for each of the two. All cases where the square root is accurate, i.e., exact All cases where the square root is ...
2
votes
2answers
922 views

defining recursively a function with multiple if conditions

I am trying to recursively define a function which satisfies the following system of equations and which depends on two parameters $n$ and $l$, $$ \begin{align} A(x, n, l) &= F[ A(x,n-1,l) ]\\ A(...
2
votes
2answers
141 views

Problem with the output of a function I program

(This is the function that I programmed) Zm2[Z_, nk_] := (zm2 = 0; For[i = 0, i < Length[Z], i++, zm2 += nk[[i]] *Z[[i]]* Z[[i]];]; Return[zm2];); (...
2
votes
1answer
85 views

Is it possible to use FormObjects and FormFunction in a stand-alone notebook?

I have been looking at the FormObject and FormFunction. Can FormObject and ...
2
votes
2answers
168 views

Expressions containing globally undefined symbols inside a function where they are defined

Consider the following code. f[a_,b_]:=x; Clear[a,b]; x=a+b; f[1,2] It returns a+b. However, from a certain viewpoint, one ...
2
votes
1answer
266 views

How to represent the lines that are formed by the intersection of two planes?

I am trying to set up Brillouin zone and representing the lines that are formed by the intersection of two planes is part of my step. I have tried the sample sections from the graphics guide book, but ...
2
votes
1answer
191 views
2
votes
1answer
106 views

Map and Scan ignore HoldFirst

I am trying to write a simple function that takes a list of data and outputs it to a file. I'd like the name of the file to be the same as the variable that holds the list. It seems that giving a ...
2
votes
1answer
333 views

Is it possible to treat starting values as variables?

I have a problem where I am using FindRoot a gazillion times over a grid of parameters. I need to allow the starting values to vary a bit with the parameters to get it to converge. Here is a simple ...
2
votes
1answer
98 views

Clean & efficient bounding box non-intersection test

I would like a quick test to tell me that segments $ab$ and $cd$ cannot intersect in the plane. If the maximum $x$-coordinate of $a$ and $b$ is less than the minimum $x$-coordinate of $c$ and $d$, ...
2
votes
1answer
95 views

Can I use Switch with an inequality? [closed]

I'd like to have something like: Switch[x, 10, a = 3; b = 7, >10, a = 5; c = 6, _, a = 7; d = 12, b = 1]; I can't seem to get this to work.
2
votes
2answers
182 views

How to plot points with error circles on map with latitude/longitude grid

I am currently working on a project to model the location of icebergs in the northwest atlantic. When an iceberg is sighted, an error circle is plotted around it (with a bivariate normal probability ...
2
votes
1answer
114 views

Please explain this while-loop

Code: ...
2
votes
1answer
619 views

Converting a nested for loop from MATLAB

In MATLAB I have the following series of nested for loops that update a matrix. (It's not my code, but someone else's that I'm trying to replicate - I don't know ...
2
votes
1answer
171 views

Rookie mistake in defining a function with Modules?

I can't figure out what's wrong with this piece of code. I'm trying to define a function that counts the occurrences of x, y and ...
2
votes
1answer
133 views

Import a file only if it contains a certain pattern

Let's say I have three files containing: File 1: x y z 1 4 6 File 2: x y z 2 5 9 File 3: x y z 5 4 8 My goal is to import the data from a file only if in ...