GMAP Procedure

Example 20: Using Traditional Map Data While Rotating and Tilting a Surface Map

Features:

MAP= required argument referring to traditional map data

DATA= required argument referring to response data

ID statement

SURFACE statement options:: CONSTANT=; NLINES=; ROTATE=; TILT=

Data sets:

MAPS.EUROPE (map data)

SASHELP.DEMOGRAPHICS (response data)

Sample library member:

GMPROSUR

This example tilts and rotates the surface map and uses more lines to draw the surface. Not all the countries that are represented in the traditional map data set have demographic data in the response data set.

Rotating and Tilting a Surface Map with Traditional Map Data

Program

goptions reset=all border;

title1 "Population in Europe (2005)";

proc gmap map=maps.europe data=sashelp.demographics;
   id id;
   surface pop / constant=4
                 nlines=100
                 rotate=40
                 tilt=60;
run;
quit;

Program Description

Set the graphics environment.

goptions reset=all border;

Define the title for the map.

title1 "Population in Europe (2005)";

Produce the surface map. The CONSTANT= option specifies a value that is less than the default value, resulting in spikes that are narrower at the base. The NLINES= option specifies the maximum number of map lines, which gives the best map shape resolution. The ROTATE= and TILT= options adjust the map orientation to make the crowded spikes in the northeast portion of the map easier to distinguish.

proc gmap map=maps.europe data=sashelp.demographics;
   id id;
   surface pop / constant=4
                 nlines=100
                 rotate=40
                 tilt=60;
run;
quit;