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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1
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1answer
243 views

Problem with function as an argument

I want to write a function like the following: s[u_, v_, x_, val_] := u[val]/NIntegrate[u'[x] v[x] + u'[x] v'[x], {x, 0, 1}] So I can evaluate something like ...
4
votes
2answers
535 views

Optimize inner loops

I'm Mathematica newbie so please be gentle :) I have this, heavily non-optimized part of code, which I would like to speed up. I have put all matrices to be RandomReal, but in my code they take ...
0
votes
1answer
370 views

How can I make many runs of a simulation and plot all the results with one expression evaluation?

I have many cells, starting with this first cell: ...
1
vote
0answers
262 views

Return Functions from parallel execution of module

I wrote a module which numerically solves an ODE using NDSolve. The result from this is e.g. either ...
6
votes
1answer
340 views

Why is MapIndexed better than mapping over a range?

Background I'm working on an application in which I need to create and control two sets of locators. I know from reading the Mathematica documentation and certain posts on Mathematica.SE that this ...
2
votes
1answer
432 views

Cournot Equilibrium

I'm trying to determine reaction functions of a Cournot equilibrium for $n$ firms using the same optimal condition, using the fixed point method. This is the method I'm using: ...
9
votes
5answers
468 views

Incrementing a number where each digit has a different base

Let's say I have a list, for instance {10,5,3}, indicating the bases for each digit of my 3-digit number. Using this basis, if I wanted to increment {8,4,1} a couple of times, here's what I would get: ...
2
votes
0answers
153 views
4
votes
3answers
550 views

How to make brute force coding more efficient?

Hi guys and guysettes, The little Mathematica I've been using/seen so far, it seems to be all about neat "one-liners" using the underlying functions and working with lists & maps to solve issues, ...
5
votes
1answer
208 views

How to create a Hyperlink within the current Notebook?

Using “Create Hyperlink” dialog window I can create a link to a tagged cell in my notebook (it's “Destination notebook: Current notebook” radio button). Now, I can't figure it out how to create such ...
7
votes
3answers
484 views

Rewriting For loop to FoldList or similar

In CrossValidated, the answer to a question on prediction of number of viewers of Gangnam Style is given in R. I have mapped the answer directly to Mathematica: ...
7
votes
3answers
266 views

Restricted accumulation of values

Please consider the following list data. I was trying to accumulate data until the result turns positive the first time and ...
9
votes
4answers
497 views

How to implement dual numbers in Mathematica?

I wonder how can I implement dual numbers in Mathematica, so that all functions work well with them (as with complex numbers). Particularly, for each function $f$, ...
12
votes
5answers
774 views

How to improve this code for solving the “Mr.S and Mr.P” puzzle?

Mr.S and Mr. P puzzle — "Formalization of two Puzzles Involving Knowledge", McCarthy, John (1987) We pick two numbers $a$ and $b$, such that $a\geq b$ and both numbers are within the range ...
4
votes
1answer
268 views

Maximizing functions with Which statements

I'd like to be able to find the maximum value that my Capex function (see below) generates. This is a fairly simple function so I could just add it up but I have more complex functions of a similar ...
2
votes
5answers
428 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
1answer
818 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 ...
6
votes
1answer
263 views

Return a Part by Reference? (For accessing hierarchical / structured data)

Is there a way to return a part of a list by reference, for reading and writing? I want to do this so I can easily manipulate "rule-styled structured", i.e., hierarchical data that is loaded from a ...
4
votes
3answers
417 views

Generate a Combination of letters by a number

I'm trying to write a function f. example: ...
7
votes
1answer
355 views

Guides for programming CDFs

Are there any tutorials for programming high-quality CDFs, like the interactive calculus textbook presented at wolfram.com? Mathematica's Help is extremely impressive but it really does not help much ...
1
vote
2answers
256 views

Inputting two arrays for a module in Mathematica

I am relatively new to the Mathematica enviroment and not sure where I am going wrong. I have evaluated the question and understand it, but dont know how to exactly create a module for it. The ...
1
vote
1answer
456 views

Equivalent of Python's “all” function in Mathematica

The Python function def isPrime(n): return all(n % i for i in xrange(2, n)) checks if a number is a prime number by using ...
22
votes
2answers
557 views

When to use Get vs Needs

When should I use << vs Needs? I just always use Needs as ...
3
votes
2answers
142 views

Localizing Pattern Names

When I want to define a function that uses a pattern, how should I localize the pattern name (i.e., x_ localizing the symbol x)? ...
4
votes
2answers
272 views

How can I use Max[] in a function that is passed a list not find the max of the list

For most functions in Mathematica, passing them a list will call the function on each element of the list. For example: ...
3
votes
1answer
310 views

Do “objects” in Mathematica have to be declared?

A while ago I learned a trick which allows one to imitate object-oriented programming in MMA using SubValues: ...
12
votes
5answers
1k views

How can I get exactly 5 logarithmic divisions of an interval?

I'd like to get exactly 5 divisions from x to y on a log scale. Can FindDivisions do this?
0
votes
1answer
1k views

Getting imaginary data from known real data using Kramers-Kronig relations [duplicate]

Possible Duplicate: Kramers-Kronig in Mathematica I am trying to get epsilon2 (imaginary part) from known epsilon1 ...
4
votes
1answer
564 views

How to combine a set of Plots, including self-drawn Inset/Lines/Circles?

I have a set of 9 plots which should be combined into one plot. Each of these plots contains a ListContourPlot, some circles, lines and an ...
2
votes
1answer
214 views

Fighting Less::nord at the root: Any unintended consequences?

After being plagued too much by Less::nord and companions, I've decided to try to fight it at the root: The comparison operators. I noticed that typically, the bad ...
7
votes
1answer
509 views

Communication between parallel kernels

Greetings. This is my first post here, also, I am not a seasoned programmer, so any advice pertaining to coding that is not directly related to the problem (stated below) is welcome. I am having ...
14
votes
1answer
1k views

Poisson solver using Mathematica

I am looking for some help with a Poisson solver I am writing in Mathematica. The code is quite long with Arrays plugged in, so the full details can be found at http://pastebin.com/uSrSDcW6 I am ...
14
votes
1answer
311 views

Modules that initialize themselves on first call

I use a lot of functions that extract a specific data item from a file with many data items. I want these functions to load data (slow) and return the item (fast) on first call, but just return the ...
5
votes
2answers
169 views

How to silence all messages associated with a built-in symbol?

The post title's pretty much says it all... The reminder of this post just describes the little headway I made with this problem, FWIW. One would hope that ...
4
votes
2answers
757 views

Split string into sub-strings of length n [duplicate]

Possible Duplicate: Partition string into chunks How can I split a string into sub strings of length n? For example I have a string "ABCDEabcde1234" ...
6
votes
2answers
616 views

Web scraping and multi-threading in Mathematica

I'm working in some web scraping using Mathematica, and today, to speed-up the process, I used bash commands (xargs with parallel options with curl and wget) using ...
0
votes
2answers
131 views

How to avoid restart during development? [duplicate]

Possible Duplicate: How do I clear all user defined symbols? During package development things get messed up quite often. (especially when playing with notations) Is there a simple way to ...
7
votes
3answers
431 views

how to read in a file in the same directory?

Now I am writing a small package. I have written several files and put them in the same directory. And some files need to read in or include another file in the same directory. But when I simply write ...
27
votes
4answers
1k views

Are there suitable versioning systems for Mathematica notebooks?

I am considering a project using Mathematica and openCL. I know that the openCL C source code can be tracked. Has anyone used a versioning site or software so multiple developers can modify a common ...
4
votes
1answer
162 views

Transform sequential cell operations to programmatic workflow

Let's say I have a workflow that involves importing images and turning them into an animated gif. Here's how I currently have it setup: Import Images: ...
3
votes
1answer
430 views

Control over depth-first scan and breadth-first scan

Is there a way to conditionally take control/modify the flow during a depth-first scan or the breadth-first scan ? Say, for example, if a particular node if found, consider it as a leaf-node and ...
9
votes
1answer
1k views

Multi-objective genetic algorithm in Mathematica?

Is there any implementation of a multi-objective genetic algorithm for Mathematica?
4
votes
1answer
279 views

How to organize and run functions?

I am very new to Mathematica. I thought I would try it out for my first assignment in my computer science class. Until now I have only used C-base languages including C#, Java, Objective-C, and ...
3
votes
1answer
465 views

FindMinimum, NMinimize, etc. with external process

I was hoping to be able to use MMA's minimization power to work with an external process. I want to minimize the function 'TryThisNumber[x_]' which sends the value of x to something external and gets ...
1
vote
2answers
242 views

How to insert an expression in a Mathematica program?

I need to insert a very large expression in a Mathematica program. So I first Put[large expression,"file"] and then use Block[{}, Get["file"];...] to ...
20
votes
3answers
446 views

How can I regroup elements in a list into a tree based on their values?

I have a list of elements in an outline, here is an example that is only 3 levels deep: ...
4
votes
3answers
198 views

Is it possible to replicate the “magic” of OptionPatterns[] with DynamicModule's local variables?

Creating richer interactive interfaces that are generated by a DynamicModule invariably requires more complex data structures and in particular, a larger argument ...
9
votes
2answers
183 views

How can I build an inline documentation utility?

I often have a large function to which I add inline comments, but then I can't see the forest for the trees. How can I make a tool that extracts the comments and tokens within them to generate an ...
18
votes
11answers
1k views

Generating an ordered list of pairs of elements from ordered lists

I have a pair of ordered lists. I want to generate a new ordered list (using the same ordering) of length n by applying a binary operator to pairs of elements, one from each list, along with the index ...
6
votes
2answers
172 views

Is Package development (via InitializationCells) compatible with creating new Notations (via MakeExpressions)?

Can new (lower-level) notations be readily used within package code? There are a few notational additions that might improve my code base but I'm not sure if these will end up being more trouble than ...