nil error while classifying

[will3216]

NoMethodError: undefined method map' for nil:NilClass from /Users/william/.rvm/gems/ruby-1.9.3-p547/gems/stuff-classifier-0.5/lib/stuff-classifier/bayes.rb:13:indoc_prob'

[tigerneil]

It seems the content you want to classify is empty string (i.e. ""). you should tackle this case(remove them for example)