Questions about the generation and use of compiled functions using Compile.
51
votes
6answers
3k views
List of compilable functions
Is there somewhere a list on the functions that Compile can compile, or the cases in which a particular function can be compiled that I haven't found?
I'd be glad ...
32
votes
2answers
986 views
Internal`Bag inside Compile
Since Internal`Bag, Internal`StuffBag and Internal`BagPart can be compiled down, it is a ...
58
votes
4answers
3k 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 ...
27
votes
4answers
1k views
How well does Mathematica code exported to C compare to code directly written for C?
Essentially what it says in the title. Mathematica can, IIRC, export it's code to C. How much overhead does that inflict on the code, as compared to writing it from scratch in C?
31
votes
4answers
1k views
Speeding up this fractal-generating code
I used the code below (which is a sample from this gist containing more similar code) in my answer to my own question about Mandelbrot-like sets for functions other than the simple quadratic on ...
12
votes
2answers
415 views
Efficiently collecting results inside a compiled function
When we don't know the number of results that will be generated, the usual way to collect results is Reap/Sow. Another ...
7
votes
2answers
154 views
Compiling more functions that don't call MainEvaluate
I would like to use Compile with functions defined outside Compile.
For example if I have the two basic functions F and G
F[x_] := x + 2
G[x_] := x
And I want ...
11
votes
2answers
249 views
How can I compile this function
I want to simplify my function f1 to f2, but f2 can't be compiled. How can I make it ...
10
votes
1answer
177 views
Removing calls to MainEvalute when using inlined compiled closures
This question is tightly related to the answer Shaving the last 50 ms off NMinimize.
There @OleksandR shows how inlined closures can be used to eliminate calls to ...
11
votes
1answer
291 views
Which Distributions can be Compiled using RandomVariate
Recently, Oleksandr kindly showed a list of Mathematica commands that can be compiled.
RandomVariate was part of that list. However, whether this can be compiled depends upon the distribution that is ...
10
votes
1answer
227 views
Using Apply inside Compile
In this great answer a compiled version of the Nelder-Mead algorithm is presented.
Since it works on arbitrary dimensions (i.e. arbitrary number of arguments), it has to use apply on the objective ...
11
votes
2answers
563 views
Speeding up random walk for many particles
I am trying to speed up this code for many particles to take a random walk. I'm not sure why it is so slow for such a simple task.
I got a few hints from colleagues to reduce the precision of the ...
8
votes
1answer
234 views
Why is MainEvaluate being used when LinearSolve can be compiled?
According to this question LinearSolve can be Compiled. However, CompilePrint shows a MainEvaluate but no-warning is generated. It appears that LinearSolve is not ...
-5
votes
3answers
625 views
Problem with Compile Function
I am attempting to Compile this function which is used to calculate a elastic collision in two dimensions. The two first coordinates of each list are the position ...
13
votes
1answer
518 views
What technical obstacles prevent all Mathematica code compiling to C
The following represents an attempt at a very simple view of the levels in Mathematica code:
We have had lots of questions about deployment and compiling Mathematica code to C. Some of these for ...
13
votes
1answer
228 views
Using Boost with CreateLibrary
I was looking at the answer of Leonid of Faster alternatives for DayOfWeek and wanted to see how hard it would be to do something similar in C++ using an external library like Boost. I tried to ...
13
votes
3answers
271 views
Quick multiple selections from a list
What is the fastest way to make multiple selections from a list? Compiled methods included.
For example, here are two methods for selecting a subset, compared:-
...
15
votes
3answers
359 views
How to force Compile to return multiple results?
I would like to return two separate values from a compiled function, but Mathematica refuses to use the compiled version. Here is a narrowed-down example:
...
11
votes
1answer
165 views
Is it possible to use Compile on a function with optional arguments?
My Mathematica is a little rusty, so apologies in advance. I think my problem is quite simple, but I can't seem to find the answer on my own!
Simple example : ...
10
votes
2answers
152 views
Avoiding MainEvaluate in a CompiledFunction to fetch “global” variables
I'm trying to write a simulation using Mathematica 8.0. Since I will most likely be doing the same operation over and over again, I'm trying to Compile whatever I ...
10
votes
1answer
521 views
How to install and configure Intel C++ Compiler for Mathematica correctly?
I wish to try the trial version of the latest Intel C++ Compiler for Windows with Mathematica. I have downloaded the current version of Intel® C++ Composer XE 2011 for Windows and installed only the ...
7
votes
1answer
162 views
Compiling Map over expression that yields a ragged array
I'm trying to speed up a function that looks in the neighborhood of each 3D point in a large dataset and finds all the points within 1 unit in each direction, x, y, z.
I've started by using ...
11
votes
2answers
119 views
How do you determine the optimal autocompilation length on your system
When you pack lists there is an overhead therefore packing a list with, say, 2 elements is likely to cost more than you get back in efficiency. Mathematica has default list lengths for which functions ...
10
votes
3answers
426 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:
...
6
votes
1answer
194 views
How to compile Map and MapAt
I have a long list (say, million of elements, like this one:
{{{1.0, 2.0}, 3}, {{4.0, 5.0}, 6},...}
I would like to compile a function ...
5
votes
2answers
752 views
How to use a matrix variable for a compiled function
I want to compile the following function which takes a matrix variable.
...
7
votes
2answers
392 views
Working with large data, pass-by-reference, compiled functions
I think I know the answer to this, but after two days of Googling, this is my last effort before going down an unwanted path...
I have a function that takes lots of large data as arguments as well as ...
3
votes
2answers
235 views
Can SetDelayed (:=) be compiled?
Is it possible to put an If statement as below within a compile (see below)? I received a warning about SetDelayed.
...
0
votes
2answers
435 views
nested numerical integration: not valid limits?
I encountered an error when I was hoping for some Mathematica (8.0.4) magic sparing me to code up numerical integration, function approximation and root-finding myself. The broader context and the ...
