GINSIDE Procedure

PROC GINSIDE Statement

The GINSIDE procedure compares a data set of X and Y coordinates to a map data set containing map polygons and determines whether the X and Y points fall inside or outside of the map polygons.
Requirement: Three data sets are required: a data set containing points, a map data set, and an output data set.

Syntax

PROC GINSIDE
DATA=points-data-set
MAP=map-data-set
OUT=output-data-set
< INSIDEONLY>
<INCLUDEBORDER>;

Summary of Optional Arguments

includes points that are on the border of a polygon in the output data set.
causes the output data set to contain only points that are inside the map polygons.

Required Arguments

DATA=points-data-set
specifies an input data set that contains the X and Y coordinates of the individual points that are being compared to the map polygons.
Note:If this data set contains the same ID variable (or variables) as does the map, the value should be set to MISSING so that the points are not considered to be part of the boundary of the polygon.
MAP=map-data-set
specifies the map data set that contains the polygons that you want to compare the points in the input data set to. This data must conform to the rules for a map data set and contain variables X and Y and one or more ID variables. The ID statement should name that variable or variables.
Restriction:The X and Y values in the input data set must be in the same projection system and units as the X and Y in the map data set. So, if the map data set has unprojected X and Y values in radians, then the point data set X and Y variable values must also be unprojected and in radians.
OUT=output-data-set
specifies the output data set for the GINSIDE procedure. The output data set contains all of the observations and variables from the input data set, and an ID variable is added.

Optional Arguments

INCLUDEBORDER
includes points that are on the border of a polygon in the output data set. If any points are on the border of a polygon, then the output data set includes a variable named _ONBORDER_. If the value of _ONBORDER_ is 1, then the point is located on the border of a polygon.
Note: If a point is on the border between multiple polygons, then the point is assigned to the ID of the first polygon whose border it shares (that is, the polygon that is processed first from the map data set).
INSIDEONLY
causes the output data set to contain only points that are inside the map polygons. By default, the data set contains all points.