56 views

### How to compile gather [duplicate]

First question，How to Compile this？ gather[data_]:=Gather[data, Mod[#1, 3] == Mod[#2, 3] &] I dont know why this is wrong. ...
54 views

### Compiled version of interpolation function slower non-compiled version [duplicate]

Consider this code: ...
51k views

### Where can I find examples of good Mathematica programming practice?

I consider myself a pretty good Mathematica programmer, but I'm always looking out for ways to either improve my way of doing things in Mathematica, or to see if there's something nifty that I haven't ...
6k views

### Struct equivalent in Mathematica?

I really miss having something like a struct in Mathematica. I know of (and regularly use) a couple of programming techniques which feel like a ...
6k views

### How to compile effectively?

What are the best practices of compiling functions? I understand that this is a vague question, but let me list some aspects that might trigger useful answers. Some of these have already been answered ...
787 views

### Efficient conditional Mean[] on a large data set

Consider a list, AK6, that has 382 sublists of length varying from 2500 to 3000. Each "subsublist" is as such : ...
2k views

### InternalBag inside Compile

Since InternalBag, InternalStuffBag and InternalBagPart can be compiled down, it is a ...
687 views

### Is using undocumented functionality a Bad Idea™?

Mathematica has a lot of very useful undocumented features. For example a hash table, a built-in list of compilable functions, additional options to CurrentValue, ...
724 views

### Function does not compile with Greater in it

I have to speed up a matrix-calculation and would like to use Compile for it, though it fails and produces an unknown error message: ...
435 views

### Combining the second elements of a set of ordered pairs based on their first element [duplicate]

I have a large set of ordered pairs and I am trying to add the second elements together for any group of pairs that has the same first element. For example my data looks like: ...
1k views

### List of Parallelize[]-able functions

The question is clear and is inspired by this question and the first comment on this question. Although there are many tricks for parallelizing things that are not ...
867 views

### Axis/Angle from rotation matrix

With r=RotationMatrix[a,{x,y,z}] I can compute a 3D rotation matrix from axis/angle representation. Given a 3D rotation matrix ...
379 views

### Relational joining of tables

A common thing to want to do with data is to combine it (at least I thought this was a common thing). In SQL there is the idea of table joins "select id,v1,v2 from A,B where A.id=B.id" kind of thing. ...