add clip-2009.awk

contours/clip-2009.awk

@@ -0,0 +1,7 @@
+#!/usr/bin/awk -f
+
+# this file works with SEZP from circa 2009, where x coordinate (the 6-digit one)
+# is first, and the field separator is ' ' or more spaces.
+$1 > xmin && $1 < xmax && $2 > ymin && $2 < ymax {
+    print $1 "," $2 "," $3
+}