docs: public static boolean blockAligned( int blockLength , DSubmatrixD1 A ) {
          if( A.col0 % blockLength != 0 )
              return false;
          if( A.row0 % blockLength != 0 )
              return false;
  
          if( A.col1 % blockLength != 0 && A.col1 != A.original.numCols ) {
              return false;
          }
  
          if( A.row1 % blockLength != 0 && A.row1 != A.original.numRows) {
              return false;
          }
  
          return true;
      }