docs: public static double elementMin( DMatrix6 a ) {
          double min = a.a1;
          if( a.a2 < min ) min = a.a2;
          if( a.a3 < min ) min = a.a3;
          if( a.a4 < min ) min = a.a4;
          if( a.a5 < min ) min = a.a5;
          if( a.a6 < min ) min = a.a6;
  
          return min;
      }