To do lemmatization in R, I executed code below library("koRpus") tagged.results <- treetag(c("run", "ran", "running"), treetagger="manual", format="obj", TT.tknz=FALSE , lang="en", TT.options=list(path="C:/Program Files/TreeTagger", preset="en")) tagged.results at TT.res and got some error >source('D:/Rprograms/lemanew.R') Assuming 'UTF-8' as encoding for the input file. If the results turn out to be erroneous, check the file for invalid characters, e.g. em.dashes or fancy quotes, and/or consider setting 'encoding' manually. Error in matrix(unlist(strsplit(tagged.text, "\t")), ncol = 3, byrow TRUE, : 'data' must be of a vector type, was 'NULL' In addition: Warning message: running command 'C:\WINDOWS\system32\cmd.exe /c type C:\Users\SULOCH~1\AppData\Local\Temp\Rtmp2De3bl\tokenize5044ef851b9.txt | grep -v '^$' | C:\Program Files\TreeTagger\bin\tree-tagger.exe C:\Program Files\TreeTagger\lib\english-utf8.par -token -lemma -sgml -pt-with-lemma -quiet | perl -pe 's\\tV[BDHV]\\tVB\;s\IN\\that\\tIN\;'' had status 255 i am not understanding what this error is, could someone tell what it is?? and please send any other code to do lemmatization ,which will give correct output [[alternative HTML version deleted]]