1.Create a new Adobe Illustrator document.
2.Import the ukrail.gen file from the Tutorial Data folder and specify British National Grid as the coordinate system. It is located under Projected > Europe > United Kingdom.
3.Select all objects in the ukrail_line layer and click the Simplify Art button on the MAPublisher toolbar.
4.In the Simplify Art dialog box, choose the Douglas-Peucker method, enter 2000 in the Proximity box and choose Meter in the Units drop-down list.
5.Click Preview to see a preview of the simplified data with the current settings.
Notice that the Simplify Art tool will simplify 17,186 vertices to 8,756 vertices (a vertex reduction of 50%.)
6.Click OK to start the simplification process.
The selected art is now simplified based on a proximity value of two kilometers (2000 meters)
7.Close the document without saving.