shpmrg

README

shpmrg

shpmrg is a multithreaded utility for working with shapefiles.

The utility is simplistic and assumes all the shapefiles have the same fields and types of objects. It will not work if a shapefile mixes points and polygons, for example. Different attribute fields between shapefiles should be handled, but may not work perfectly.

Usage

Releases are available for mac, windows and linux at:

• https://github.com/AQUAOSOTech/shpmrg/releases

Example of merging shapefiles

Get shapefiles in the folder "myshapefiles" and extract into the file "output_file.shp"

shpmrg -i myshapefiles/*.shp -o output_file.shp merge

Total shapes processed: 10000
Finished /Users/jpx/myshapefiles/a.shp ( 1 of 3 )
Finished /Users/jpx/myshapefiles/b.shp ( 2 of 3 )
Total shapes processed: 20000
Total shapes processed: 30000
Total shapes processed: 40000
Total shapes processed: 50000
Finished /Users/jpx/myshapefiles/c.shp ( 3 of 3 )
Processed 51002
Done

Note: this program consumes approximately 2 CPU cores and is primarily limited by disk speed.

Example of extracting attributes into CSV

Get shapefiles in the folder "myshapefiles" and extract into the file "attrs.csv"

shpmrg -i myshapefiles/*.shp -o attrs.csv extract-attrs

Total shapes processed: 10000
Finished /Users/jpx/myshapefiles/a.shp ( 1 of 3 )
Total shapes processed: 20000
Finished /Users/jpx/myshapefiles/b.shp ( 2 of 3 )
Total shapes processed: 30000
Total shapes processed: 40000
Total shapes processed: 50000
Finished /Users/jpx/myshapefiles/c.shp ( 3 of 3 )
Processed 51002
Done

Note: this program consumes nearly all CPU, but is partly limited by disk speed.

Shape Type flag -t

By default, the utility expects the shapes to be polygons. The -t < integer > flag allows this to be changed.

The list of types is at https://godoc.org/github.com/jonas-p/go-shp#ShapeType

Here is a recent list, but this may change:

Shape	int
NULL	0
POINT	1
POLYLINE	3
POLYGON	5
MULTIPOINT	8
POINTZ	11
POLYLINEZ	13
POLYGONZ	15
MULTIPOINTZ	18
POINTM	21
POLYLINEM	23
POLYGONM	25
MULTIPOINTM	28
MULTIPATCH	31

License

MIT

Copyright (c) 2018 - present AQUAOSO Technologies, PBC

See the LICENSE file in this repository.

Credits to:

• https://github.com/jonas-p/go-shp