First_node

Network functions first node

syntax

• first_node(arc_polygon_dataitem)

definition

first_node(arc_polygon_dataitem) results in a point data item with the coordinates of the first point of an arc or polygon of argument arc_polygon_dataitem.

description

Use the arc2segm function to split an arc into segments.

applies to

data item arc_polygon_dataitem with fpoint or dpoint value type and composition type type arc or polygon.

example

attribute<fpoint> first_node (Road) := first_node(road/geometry);

road/geometry	first_node
{2: xy(112631; 399246) xy(111866; 398599)}	xy(112631; 399246)
{3: xy(111866; 398599) xy(111924; 399495) xy(111524; 401801)}	xy(111866; 398599)
{2: xy(114921; 401529) xy(114823; 398584)}	xy(114921; 401529)

domain Road, nr of rows = 3

see also

• last_node