Carrot2

Carrot2 is an Open Source Search Results Clustering Engine. It can automatically organize small collections of documents, e.g. search results, into thematic categories. Carrot2 is a library and a set of supporting applications you can use to build a search results clustering engine. Such an engine will organize your search results into topics, fully automatically and without external kowledge such as taxonomies or preclassified content.

Carrot2 integrates very well with both Open Source and proprietary search engines. Apart from the two main specialized document clustering algorithms( Suffix Tree Clustering and Lingo), Carrot2 offers ready-to-use components for fetching search results from various sources including GoogleAPI, Bing API, eTools Meta Search, Lucene, SOLR, and more. Carrot2 is implemented in Java, but a native C# / .NET API is also available.

Other non-Java platforms, such as PHP or Ruby, can call Carrot2 clustering through its REST interface. Carrot2 ships with a simple web application and Graphical User Interface(GUI) application for tuning clustering for specific collections.The architecture of Carrot2 is based on processing components arranged into pipelines. Two major groups or processing components in Carrot are: document sources and clustering algorithms.

Carrot2 offers components for fetching data from search engines that provide the required APIs (for example Microsoft Bing or PubMed), as well as other sources of documents like Lucene, Apache Solr or ElasticSearch.