@Override public String toString(){
  StringBuffer text=new StringBuffer();
  text.append("attributes " + attributesToString() + "\n");
  text.append("number of instances " + getInstNums());
  return text.toString();
}

@ Override public String toString ( ) { StringBuffer text = new StringBuffer ( ) ; text . append ( "attributes " + attributesToString ( ) + "\n" ) ; text . append ( "number of instances " + getInstNums ( ) ) ; return text . toString ( ) ; }
make a string from the cluster features .
