{"id":1659,"date":"2019-08-04T14:42:21","date_gmt":"2019-08-04T09:12:21","guid":{"rendered":"https:\/\/www.rangakrish.com\/?p=1659"},"modified":"2019-08-04T14:43:57","modified_gmt":"2019-08-04T09:13:57","slug":"generating-poetry-in-prolog","status":"publish","type":"post","link":"https:\/\/www.rangakrish.com\/index.php\/2019\/08\/04\/generating-poetry-in-prolog\/","title":{"rendered":"Generating Poetry in Prolog"},"content":{"rendered":"

In an earlier article<\/strong><\/em><\/a>, I showed how we can generate poetry (with limitations, of course!) using my iLangGen<\/strong><\/em> framework. That implementation (in Lisp<\/strong><\/em>) made use of iLexicon<\/strong><\/em>, a large dictionary of English words, which I have been building over the years. I subsequently ported iLexicon<\/strong><\/em> to Prolog<\/strong><\/em> and it now works well in SICStus Prolog<\/strong><\/em><\/a>. In fact, I am quite pleased with its performance!<\/p>\n

I decided to experiment with poetry generation using DCG<\/strong><\/em><\/a> (Definite Clause Grammars) in Prolog<\/strong><\/em>, simultaneously taking advantage of iLexicon<\/strong><\/em> to provide vocabulary for the generation task. Today’s article describes my approach.<\/p>\n

The following code fragment sets up some English words for use in the generation.<\/p>\n

\"Setting<\/a>
Setting up the Vocabulary<\/strong><\/figcaption><\/figure>\n

As you can see (lines 22 – 27), I am pre-fetching some words from iLexicon<\/strong><\/em> and caching them for faster access during generation. This additionally facilitates randomizing the words.<\/p>\n

The following shows the DCG<\/strong><\/em>\u00a0rules for a simple grammar, capable of generating a single line of a poem. To add flexibility and variety, I have defined three “patterns”<\/strong><\/em> that can be used as templates for the generation.<\/p>\n

\"DCG<\/a>
DCG Rules<\/strong><\/figcaption><\/figure>\n

The main clauses used to generate the poem are shown below.<\/p>\n

\"Generation<\/a>
Generation Logic<\/strong><\/figcaption><\/figure>\n

I have defined two ways to generate a poem:<\/p>\n