shpsort.txt

============================= ABOUT =========================================== 

The program "shpsort" is a standalone program for sorting shapefiles
on one or more fields (including the pseudofield "SHAPE") and outputing
the results.  People may find it useful for forcing drawing order.

============================= AUTHOR ==========================================

Eric G. Miller
California Department of Fish and Game
2004-06-30

============================= USAGE ===========================================

shpsort <INFILE> <OUTFILE> <SORT_FIELD;SORT_FIELD...> {SORT_ORDER;SORT_ORDER...}

============================= DETAILS =========================================

INFILE		The input shapefile

OUTFILE		The output shapefile

SORT_FIELD	Any attribute field of the shapefile, including "SHAPE"

SORT_ORDER	Specify "ASCENDING" or "DESCENDING" for each SORT_FIELD.
		This field is optional, and is assumed to be ASCENDING
		unless the exact word "DESCENDING" is specified (case
		matters).

	When sorting on the "SHAPE" the records are sorted as follows:

	*  Null shapes are treated as any other null field and will
	   sort to the top in ASCENDING mode.  A warning is issued
	   for each null shape encountered.
	*  POINT, POINTM, POINTZ, MULTIPOINT, MULTIPOINTM, MULTIPOINTZ
	   and MULTIPATCH are all sorted by the maximum "Y" value of
	   their envelopes (not particularly useful).
	*  POLYLINE, POLYLINEZ and POLYLINEM are sorted by total 2d 
	   shape length.
	*  POLYGON, POLYGONZ and POLYGONM are sorted by the 2d shape 
	   area. Shapes are assumed to be in canonical ordering, so that
	   the area of interior rings (if any) is subtracted from the
	   area of exterior rings.