/** Selects roads to assign class

reselect roads07 arcs road_width ge 2 and road_width lt 4

reselect roads07 arcs cutbank_height ge 0 and cutbank_height lt 2.5

reselect roads07 arcs cutbank_slope ge 0 and cutbank_slope lt 5

reselect roads07 arcs drainage_ditch_d ge 0 and drainage_ditch_d lt 12.5

reselect roads07 arcs drainage_ditch_w ge 0 and drainage_ditch_w lt 50

calculate roads07 arcs class = 1

clearselect