title: Generate a libsvm formatted data from text file
body: <p>Firstly, i'm very poor in data pre-processing. I was looking for WebKB data in libsvm format. Later after searching a lot over the internet, i came across this data obtained after stemming and stop-word removal. The format is as follows,<br>
  Each line represents a vector and the first word in each file contains the class name followed by some list of words which forms the feature delimited by spaces.<br>
  How do i convert such a text file to lib-svm format? Is there any Weka or Matlab tool to construct it? </p>