geom_npoint geom_nsegment get_srid_ways MAXNPOINTLEN npoint_cmp npoint_eq npoint_ge npoint_geom npoint_gt npoint_hash npoint_hash_extended npoint_in npoint_le npoint_lt npoint_make npoint_ne npoint_out npoint_position npoint_route npoint_set npoint_srid npoint_to_nsegment npointarr_geom nsegment_cmp nsegment_end_position nsegment_eq nsegment_ge nsegment_geom nsegment_gt nsegment_in nsegment_le nsegment_lt nsegment_make nsegment_ne nsegment_out nsegment_route nsegment_set nsegment_sort_cmp nsegment_srid nsegment_start_position nsegmentarr_geom nsegmentarr_normalize nsegmentarr_sort route_exists route_geom route_length

nsegment_start_position() double nsegment_start_position ( const Nsegment *  ns ) Return the start position of the network segment.