public static Tree fromString(String ptbStr){
  PennTreeReader reader=new PennTreeReader(new StringReader(ptbStr));
  return reader.next();
}

public static Tree fromString ( String ptbStr ) { PennTreeReader reader = new PennTreeReader ( new StringReader ( ptbStr ) ) ; return reader . next ( ) ; }
this is a convenience function for producing a fragment from its string representation .
