Contribute to the library

Table of Contents

• Adding components
  • Adding functors (kernels, criteria and mean functions)
• Modifying the Python interface:
  • Install Cython:
  • Working with Cython:

Adding components

Thanks to the modular design, adding new components is very easy. Most of the inner functions (kernels, criteria, etc.) are designed as functors (function objects). Thus, we just need to inherit from the interface (abstract) functor or one of the existing functions. Then, we need to include the reference in the corresponding factory module and the new functor would be automatically integrated, including advanced usage (for example: annealing).

Although it would be more efficient to use a template system. The functors are instantiated dynamically using a factory model. This allows great flexibility without recompiling the library, which is specially important while using interpreted languages (Python, Matlab, etc.).

Adding functors (kernels, criteria and mean functions)

The three elements follow the same structure. The interface (abstract class) and the factory model are defined in the *_functors.hpp and *_functors.cpp files, respectively.

Then, there are two types of functors: atomic and combined. Atomic functors are used to define directly a function (e.g.: a Gaussian kernel) and they return a value. Combined functors are used to combine 2 or more functors (e.g.: sum of kernels), which can be atomic or combined (e.g.: a sum of products of kernels).

Combined kernels and mean functions only allows binary expressions -2 elements- as they represent associative functions (sum, product, etc.). Meanwhile combined criteria support any number of elements (see cHedge function in Combined criteria).

Finally, add the corresponding register with the new function name in the Factory model in *_functors.cpp

Modifying the Python interface:

Read this part only if you need to modify the Python interface.

Install Cython:

First, you need to install Cython:

In Ubuntu/Debian, you can get it by running:

>> sudo apt-get install cython

In MacOS you can install macports and run:

>> sudo port install py27-cython

Or we can download it from the website: http://cython.org

Working with Cython:

The interface is defined in python/bayesopt.pyx file, which is written in Cython, a mixture of C and Python code. For more information, check the online documentation http://docs.cython.org/

Then, you need to run the Cython compiler.

$ cython --cplus bayesopt.pyx

which generates the file python/bayesopt.cpp, which can be directly used in the library. Python would only find the library if it is called exactly bayesopt.so