dt = Current Data Table();
m = Mean( dt[0, 2 :: 3] );
Column( "S" ) << Formula( If( Abs( H - m ) > Abs( L - m ), L, H ) );
dt << run formulas;
Column( "S" ) << deleteFormula;
ar = dt << GetAsMatrix( {4, 1} );
{Beta, VarBeta} = Least Squares Solve( ar[0, 1], ar[0, 2] );
x = round(Beta[1],0);
Thanks Experts!