This tag is intended for the review and improvement of style for already functioning code. It not meant to change the objective of the code.

learn more… | top users | synonyms

35
votes
9answers
6k views

Programming paradigm change

I'm new to Mathematica, I've been learning by myself, and, being a Java developer for some time, it makes it hard to adapt. I've tried to solve a Reddit challenge, and I came up with this solution: <...
34
votes
0answers
1k views

Fast Spherical Harmonics radiative transfer

This is a rather specific question and I apologize for spamming you with some lengthy code. But it could be interesting for some reader and maybe you can help out, so please bear with me. I am using ...
30
votes
1answer
2k views

May the Fourth be with you

Happy Star Wars day. I was playing around with the image manipulation functions in Mathematica in an attempt to recreate the Star Wars crawl. There's an HTML/CSS implementation which is in my ...
26
votes
7answers
1k views

Splitting words into specific fragments

I am looking into splitting words into a succession of chemical elements symbols, where possible. For example: Titanic = Ti Ta Ni C (titanium, tantalum, nickel, carbon) A word may or may not be ...
25
votes
2answers
613 views

Copying one symbol into another

I would like to know how can I completely copy one Symbol to another. When I say copy, a refer to UpValues, DownValues, ...
23
votes
1answer
806 views

Strategies for solving problems involving searches

As an example of a search-oriented problem, consider finding all constrained $n$-colorings of a graph. An "$n$-coloring" associates one of $n \ge 1$ colors to each vertex in such a way that no edge ...
19
votes
1answer
349 views

Segmentation of sunspots

I recently went for a walk with my camera and snapped a few pictures of the sun. The pictures didn't turn out too well, but this was to be expected without a telescope. I thought it might be a nice ...
15
votes
8answers
2k views

How to avoid procedural loops in this example?

I want to iterate over a list, and return the index as long as I found the first element satisfying my condition. Written in a for loop: ...
15
votes
4answers
729 views

Button evaluation inside DynamicModule

Someone know why this Button works when clicked: ...
15
votes
3answers
301 views

How to check the validity of an option value

I have a user-defined function, func, which takes the following form: func[arg1, arg2, options] Here is the actual code ...
15
votes
1answer
2k 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
9answers
714 views

Thread over list in different levels

I have these two lists, both with the same length in the first dimension: ...
14
votes
3answers
396 views

Clever use of DownValues, or failure to understand the “Mathematica Way.”

I needed to look at the changes in the values of about 4000 items from one year to the next. I have a table with identifiers and values for each year. Not all of the items are in each list. The ...
13
votes
7answers
848 views

How to sort digits in a string while keeping other characters untouched?

Now there is a string with digits and letters, for instance, "95uge678r3gi89hgfe30kgh063d51". And the expected output is ...
13
votes
2answers
761 views

Parsing a CSV file using Interpreter

The new Interpreter functionality in version 10 looks like it has the potential to make parsing custom data formats very easy. I'm trying to create a CSV parser. ...
13
votes
2answers
749 views

What's the most “functional” way to do Cholesky decomposition?

I can do Cholesky in a procedural style, such as: ...
12
votes
3answers
916 views

Simpler way to fill date gaps with zero values

One basic problem when working with data like sales and dates is the case where you dont't have sales in all days, so you have to fill it to take information as average or to make a plot. See this toy ...
11
votes
1answer
410 views

How to visualize pattern matching process?

I want a function that does the same job like ReplaceRepeated, and can make the matching process visible. I searched the Internet but didn't find any existing code ...
11
votes
1answer
245 views

Extract what symbol is set by SetDelayed, Set, TagSet, UpSet, SetAttributes, etc

One of the recent features of the Mathematica Plugin for IntelliJ IDEA (www.mathematicaplugin.halirutan.de) is a Structure View which let's you see information about several definitions that are done ...
11
votes
1answer
161 views

The equivalent of dplyr mutate with Dataset

In R, there is a package "dplyr" that works on data.frame objects, which is one of the origins of the Mathematica Dataset construct. One of the things dplyr can do is "mutate" the columns of a data....
10
votes
1answer
195 views

How to construct the RHS of Wick's theorem

I've been trying this for a few days now, but I just can't seem to find an efficient (speed-wise) functional way to code the following task. Context: I would like to construct an expressions that is ...
9
votes
1answer
642 views

TemporalData frequency option as in R

I'm studying R, and am very impressed by the simplicity of some commands and in the way R handles temporal data. For example, in R, if you have some one-dimensional temporal data, you can easily ...
8
votes
4answers
699 views

Loop optimization

I wrote this to generate a 6D distribution of particles. ...
8
votes
2answers
982 views

Speed up Mathematica code involving Convolve

I'm trying to plot the averaged autocorrelation function of a random wire profile $\xi(x)$ which is build from unitsteps which are each L units long. To calculate the average I'm generating nMax ...
8
votes
2answers
651 views

Feedback on Functional Programming: Propagation of uncertainty

Lately I've been trying to use functional prgramming and tried to implement the gaussian propagation of uncertainty (without correlation) in an elegant way, here is the outcome: ...
7
votes
3answers
642 views

Mathematica style (drawing cubes)

I wanted to draw (lattice-aligned) unit cubes inside a sphere with a given radius centered on the origin, so I wrote this program: ...
7
votes
2answers
236 views

Efficient Lloyd Sampling of Images

I want to sample a grayscale image so that every voronoi cell contains approximately the same total intensity using lloyd sampling. My current code is kind of slow and I was hoping for some advice to ...
7
votes
1answer
344 views

Porting code from MATLAB

I'd like to switch from MATLAB to Mathematica for my research in digital signal processing. I used Mathematica a lot during the '90s but I haven't used it since then, so I might as well be a complete ...
7
votes
1answer
282 views

Selecting a list from a list of lists

In working through Programming Paradigms Via Mathematica (A First Course) I have come across this two part question: A permutation of length "n" is a list of the first n positive integers in ...
7
votes
1answer
190 views

Simpler code evaluating Dickman's function?

I've read here that Mathematica 10 can Obtain symbolic solutions to delay differential equations. Would that help in numericaly evaluating Dickman's function $\rho(u)$ ? It is a delay differential ...
7
votes
2answers
1k views

Elegant way to handle columns operations

Inspired by this question from @sjdh and by my recurrent use of columns operations in database sets, I was looking for one way to make columns operations more symetric, so I can handle with matrix and ...
6
votes
2answers
182 views

Looking for feedback on this function

I'm not sure this is an appropriate question; if not, I'm sure someone will close it :) I've got the following function, listed below; its job is to accept a graph (function) presented either as a ...
6
votes
2answers
145 views

Plot of The RiemannSiegelZ Function

I would appreciate your help to visualize the of the following function RiemannSiegelZ[x] with this range. { 18154980120849865 , 18154980120849885 } I tried this: ...
6
votes
1answer
157 views

Path construction using `Nearest` shows ill behavior?

I have a dataSet that I'm trying to sort choosing a starting point and going to its nearest neighbor, and then to its nearest neighbor and so on. To do so, I've ...
6
votes
1answer
145 views

How can I do a two dimensional Fold? [closed]

I'd like to Fold over higher dimensional objects than lists. Semantically, the format would be something like ...
6
votes
0answers
186 views

Fine tuning compiled code that computes dilogarithm function

As an exercise of writing a good Compile function, I want to do the simple task of coding a routine that outputs the real part of the dilogarithm function ...
5
votes
6answers
2k views

Why is this Mandelbrot set's implementation infeasible: takes a massive amount of time to do?

The Mandelbrot set is defined by complex numbers such as $z=z^2+c$ where $z_0=0$ for the initial point and $c\in\mathbb C$. The numbers grow very fast in the iteration. ...
5
votes
3answers
2k views

Using DSolve to solve for x[t,parameter]

I'm trying to solve an ODE with two independent variables (a cannon firing from a cliff incorporating wind resistance dependent on velocity). I've tried the following for the x-component: ...
5
votes
1answer
121 views

Composition vs serial assignment, which performs better?

I have a giant block of code that manipulations an expression in many different ways. Currently it looks like ...
5
votes
2answers
423 views

Code elegance and compactness. Help needed with Map, Apply

I need some help with code optimization and compactness. I have a set of two-dimensional points and I can use the Mathematica function FindClusters to find 4 clusters. I'd like to plot the points ...
5
votes
2answers
1k views

How to create a simple interface to get file path and execute some code on it?

I need to create a simple user interface to choose one file in the notebook directory, import it and execute some functions on the imported data. For the first version I created this code: ...
5
votes
0answers
212 views

Forecasting problem with Geometric Brownian Motion in Wolfram Mathematica [closed]

I'm a full time undergraduate student from Peru, and I'm trying to use the Geometric Brownian Motion example used in the help section from Wolfram Mathematica in order to forecast future stock prices,...
5
votes
0answers
149 views

Better way to compute triple (or higher order) convolution

I have an identity that I want to verify: $$\sum_{i+j+k\ge 2}\binom{n}{i,j,k}{B_{N,i}B_{N,j}B_{N,k}}=\left(\frac{2N^2+n^2-3nN}{2N^2}\right)B_{N,n}+\left(\frac{3n^2-2n-4nN}{2N^2}\right)B_{N,n-1}+\...
4
votes
3answers
249 views

Is there something wrong with this piece of code involving Manipulate?

I am playing around with the Manipulate sentence. I think the following code is right, and actually Mathematica 9.0 doesn't return any error message, but I am ...
4
votes
2answers
129 views

Sound synthesizer using Manipulate

Sound synthesizers, both digital and analog, often include a parameter section for shaping the amplitude of a sound wave over time. This parameter section is commonly known as an "ADSR EG" (attack, ...
4
votes
2answers
203 views

Generate lists that satisfy a condition in an efficient way

The following code produces lists of sublists with maximum length 5 that shuffle zeros around an ordered list (here {1,2}). It produces all permutations while ...
4
votes
2answers
257 views

Finding large Collatz Sequences, trying to improve speed

Background: I am already very much in love with Mathematica but I am also a novice. So far I have only gathered experience in procedural programming in Python. Generally speaking I am trying to ...
4
votes
3answers
2k views

How to fix BodePlot that comes with Mathematica?

I am using Mathematica to go through the examples and exercises on the book Modern Control Systems, 6th edition by Dorf. On page 605, there is a table (Table 8.5) with the Bode plot for several ...
4
votes
1answer
262 views

Symbolic bit vectors

I'd like to see how addition and xoring bitvectors mix together. To do this, I implemented (a primitive) vec_add and vec_xor: ...
4
votes
3answers
147 views

Tips to write more readable code [closed]

What are some tips to write a more readable code? For example in C, tab is your friend. You can also declare variables in a way such that you can read the code easily later on. In Mathematica, if ...