Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help 
OGR_LAYER_ALGEBRA(1)		     GDAL		  OGR_LAYER_ALGEBRA(1)

NAME
       ogr_layer_algebra - Performs various Vector layer algebraic operations

       New in version 3.6.

SYNOPSIS
	  ogr_layer_algebra [--help] [--help-general]
			      Union|Intersection|SymDifference|Identity|Update|Clip|Erase
			      -input_ds	<path> [-input_lyr <name>]
			      -method_ds <path>	[-method_lyr <name>]
			      -output_ds <path>	[-output_lyr <name>] [-overwrite]
			      [-opt <NAME>=<VALUE>]...
			      [-f <format_name>] [-dsco	<NAME>=<VALUE>]... [-lco <NAME>=<VALUE>]...
			      [-input_fields {NONE|ALL|<fld1>,<fl2>,...<fldN>}]	[-method_fields	{NONE|ALL|<fld1>,<fl2>,...<fldN>}]
			      [-nlt <geom_type>] [-a_srs <srs_def>]

DESCRIPTION
       The  ogr_layer_algebra provides a command line utility to perform vari-
       ous vector layer	algebraic operations. The utility takes	a vector input
       source and a method source and generates	the output of the operation in
       the specified output file.

       NOTE:
	  ogr_layer_algebra is a Python	utility, and is	only available if GDAL
	  Python bindings are available.

       --help Show this	help message and exit

       --help-general
	      Gives a brief usage message for the generic GDAL commandline op-
	      tions and	exit.

       <mode> Where <mode> is one of the seven available modes:

	      •	Union
		   A union is a	set of features, which	represent  areas  that
		   are in either of the	operand	layers.

	      •	Intersection
		   An  intersection  is	a set of features, which represent the
		   common areas	of two layers.

	      •	SymDifference
		   A symmetric difference is a set of features,	 which	repre-
		   sent	 areas that are	in operand layers but which do not in-
		   tersect.

	      •	Identity
		   The identity	method identifies features in the input	 layer
		   with	 features  in the method layer possibly	splitting fea-
		   tures into several features.	 By default the	 result	 layer
		   has attributes from both operand layers.

	      •	Update
		   The	update method creates a	layer, which add features into
		   the input layer from	the method layer possibly cutting fea-
		   tures in the	input layer.  By default the result layer  has
		   attributes only from	the input layer.

	      •	Clip
		   The	clip  method  creates a	layer, which has features from
		   the input layer clipped to the areas	of the features	in the
		   method layer.  By default the result	layer  has  attributes
		   of the input	layer.

	      •	Erase
		   The	erase  method creates a	layer, which has features from
		   the input layer whose areas are erased by the  features  in
		   the	method layer.  By default the result layer has attrib-
		   utes	of the input layer.

       -input_ds <path>
	      Input dataset path for the operation to be performed.  For oper-
	      ations involving two datasets, this is one of the	datasets.

       -input_lyr <name>
	      Layer name of the	input_ds for which the operations have	to  be
	      performed	( Optional )

       -method_ds <path>
	      Method data set path for the operation to	be performed.  This is
	      usually the conditional data set supplied	to the operation ( ex:
	      clip , erase , update ) This is the Second data set in the oper-
	      ation ( ex : Union, Intersection , SymDifference )

       -method_lyr <name>
	      Layer  name of the method_ds for which the operations have to be
	      performed	( Optional )

       -output_ds <path>
	      Output data set path for writing the result  of  the  operations
	      performed	by ogr_layer_algebra.

       -output_lyr_name	<name>
	      Layer name of the	output_lyr_name	where the output vector	has to
	      be written. ( Optional )

       -overwrite
	      Indicates	 whether the output_ds have to be overwritten with the
	      generated	result of ogr_layer_algebra.

       -opt <NAME>=<VALUE>
	      Attributes for which the operation has to	run  on	 input_ds  and
	      method_ds.

       -f <format_name>
	      Select the output	format.If not specified, the format is guessed
	      from  the	 extension  (previously	 was ESRI Shapefile).  Use the
	      short format name

       -dsco <NAME>=<VALUE>
	      Dataset creation option (format specific).

       -lco <NAME>=<VALUE>
	      Layer creation option (format specific).

       -input_fields {NONE|ALL|<fld1>,<fl2>,...<fldN>}
	      Comma-delimited list of fields from input	layer to copy  to  the
	      output layer , if	eligible according to the operation.

       -method_fields {NONE|ALL|<fld1>,<fl2>,...<fldN>}
	      Comma-delimited  list of fields from method layer	to copy	to the
	      output layer , if	eligible according to the operation.

       -nlt <geom_type>
	      Define the geometry type for the created layer.	One  of	 NONE,
	      GEOMETRY,	POINT, LINESTRING, POLYGON, GEOMETRYCOLLECTION,	MULTI-
	      POINT, MULTIPOLYGON, GEOMETRY25D,	POINT25D, LINESTRING25D, POLY-
	      GON25D, GEOMETRYCOLLECTION25D, MULTIPOINT25D, MULTIPOLYGON25D.

       -a_srs <srs_def>
	      Assign an	output SRS, but	without	reprojecting

	      The coordinate reference systems that can	be passed are anything
	      supported	 by  the  OGRSpatialReference.SetFromUserInput() call,
	      which includes EPSG Projected, Geographic	or Compound CRS	 (i.e.
	      EPSG:4296),  a well known	text (WKT) CRS definition, PROJ.4 dec-
	      larations, or the	name of	a .prj file containing a WKT CRS defi-
	      nition.

COPYRIGHT
       1998-2025

				 Feb 11, 2025		  OGR_LAYER_ALGEBRA(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=ogr_layer_algebra&sektion=1&manpath=FreeBSD+Ports+14.3.quarterly>

home | help