Custom function : Number of days between two dates excluding weekends

$L_Diff =  day_in_week($L_End) - day_in_week($L_Start) ; 

$L_Output = ((date_diff(  $L_End,$L_Start,'D')- $L_Diff) / 7 * 5)  + (decode(($L_Diff <5) ,$L_Diff,5))-

decode ( day_in_week($L_End)-4> 0 , day_in_week($L_End)-4 ,0)%5; 

return($L_Output);