//! Names Default To Here( 1 ); DOE( Covering Array, { Add Factor( Categorical, {"L1", "L2", "L3"}, "X1", 0 ), Add Factor( Categorical, {"L1", "L2"}, "X2", 0 ), Add Factor( Categorical, {"L1", "L2"}, "X3", 0 ), Add Factor( Categorical, {"L1", "L2"}, "X4", 0 ), Set Strength( 2 ), Make Design} );