R DocumentTermMatrix control list not working, silently ignores unknown parameters

controls, matrix, r, tm

Solution

dtmImproved <- DocumentTermMatrix(t, control=list(wordLengths=c(4, 15), 
                                   bounds = list(global = c(5,Inf))))

This solves the problem! The lack of proper documentation really mads me down (:

Problem

I have two following DTM-s: ``` dtm <- DocumentTermMatrix(t) dtmImproved <- DocumentTermMatrix(t, control=list(minWordLength = 4, minDocFreq=5)) ``` When I implement this, I see two equal DTM-s and if I open the `dtmImproved`, there are words with 3 symbols. Why doesn't the `minWordLength` parameter work? Thank you! ``` > dtm A document-term matrix (591 documents, 10533 terms) Non-/sparse entries: 43058/6181945 Sparsity : 99% Maximal term length: 135 Weighting : term frequency (tf) > dtmImproved A document-term matrix (591 documents, 10533 terms) Non-/sparse entries: 43058/6181945 Sparsity : 99% Maximal term length: 135 Weighting : term frequency (tf) ```

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