This example uses two data files, both from the USGS National Atlas, and also demonstrates an embedded legend and scalebar.
To find the categories for the legend, I used the
ogrinfo utility twice.
ogrinfo -a -summary timeznp020.shp let me see what fields were available, and
ogrinfo -a timeznp020.shp|grep SYMBOL|sort -u told me what all of the unique values were so that
I could build my
CLASS definitions in