diff --git a/lib/recommendify/jaccard_input_matrix.rb b/lib/recommendify/jaccard_input_matrix.rb
index <HASH>..<HASH> 100644
--- a/lib/recommendify/jaccard_input_matrix.rb
+++ b/lib/recommendify/jaccard_input_matrix.rb
@@ -38,7 +38,7 @@ private
     raise "error: dirty exit (#{$?})" if $? != 0
     res.split("\n").map do |line|
       sim = line.match(/OUT: \(([^\)]*)\) \(([^\)]*)\)/)
-      raise "error: #{res}" unless sim
+      raise "error: #{res}" if !sim && !(res||"").include?('exit:')
       [sim[1], sim[2].to_f]
     end
   end
jaccard: don't raise on zero item count