question: protected double [ ] libsvmToArray ( String row ) { double [ ] result ; StringTokenizer tok ; int index ; int max ; String col ; double value ; max = 0 ; tok = new StringTokenizer ( row , " \t" ) ; tok . nextToken ( ) ; while ( tok . hasMoreTokens ( ) ) { col = tok . nextToken ( ) ; index = Integer . parseInt ( col . substring ( 0 , col . indexOf ( ":" ) ) ) ; if ( index > max ) max = index ; } tok = new StringTokenizer ( row , " \t" ) ; result = new double [ max + 1 ] ; result [ result . length - 1 ] = Double . parseDouble ( tok . nextToken ( ) ) ; while ( tok . hasMoreTokens ( ) ) { col = tok . nextToken ( ) ; index = Integer . parseInt ( col . substring ( 0 , col . indexOf ( ":" ) ) ) ; value = Double . parseDouble ( col . substring ( col . indexOf ( ":" ) + 1 ) ) ; result [ index - 1 ] = value ; } return result ; }
target:  turns a libsvm row into a double array with the class as the last entry.