Extract Relevant Tag/Keywords from Text block

Question

I wanted a particular implementation, such that the user provide a block of text like:

\"Requirements - Working knowledge, on LAMP Environment using Lin

Answer 1

I did a quick review of these this morning and to my surprise one which performs best with my test phrase was written in PHP

• http://code.fivefilters.org/term-extraction
• demo: http://fivefilters.org/term-extraction/

What looked like the most professional one performed abysmally: viewer.opencalais.com

Others that were OK were (not sure what language they're written in)

• www.nactem.ac.uk/software/termine/#form
• www.alchemyapi.com/api/keyword/