function testMakeHankel()
 {
     $data = array(array(1, 2, 3, 3), array(2, 3, 3, 5), array(3, 3, 5, 7));
     $c = array(1, 2, 3);
     $r = array(1, 3, 5, 7);
     $res = new Math_Matrix($data);
     $hankel = Math_Matrix::makeHankel($c, $r);
     $this->assertEquals($res->toString(), $hankel->toString());
 }