Concatenate, also known as a vertical join, combines rows of several data tables top to bottom.
dt << Concatenate( DataTableReferences,...,Keep Formulas,
	Output Table Name( "name" ) );
dt = Open( "$SAMPLE_DATA/Big Class.jmp" );
dt << Select Where( :sex == "M" );
m = dt << Subset( Output Table Name( "M" ) );
dt << Invert Row Selection;
f = dt << Subset( Output Table Name( "F" ) );
both = m << Concatenate( f, Output Table Name( "Both" ) );
dt = Open( "$SAMPLE_DATA/Big Class.jmp" );
dt << Select Where( :sex == "M" );
m = dt << Subset( Output Table Name( "M" ) );
dt << Invert Row Selection;
f = dt << Subset( Output Table Name( "F" ) );
both = dt << Concatenate( m, f, "Append to First Table" );