1OGR_LAYER_ALGEBRA(1) GDAL OGR_LAYER_ALGEBRA(1)
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6 ogr_layer_algebra - Performs various Vector layer algebraic operations
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8 New in version 3.6.
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12 ogr_layer_algebra.py Union|Intersection|SymDifference|Identity|Update|Clip|Erase
13 -input_ds name [-input_lyr name]
14 -method_ds [-method_lyr name]
15 -output_ds name [-output_lyr name] [-overwrite]
16 [-opt NAME=VALUE]*
17 [-f format_name] [-dsco NAME=VALUE]* [-lco NAME=VALUE]*
18 [-input_fields NONE|ALL|fld1,fl2,...fldN] [-method_fields NONE|ALL|fld1,fl2,...fldN]
19 [-nlt geom_type] [-a_srs srs_def]
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22 The ogr_layer_algebra.py provides a command line utility to perform
23 various vector layer algebraic operations. The utility takes a vector
24 input source , a method source and generates the output of the opera‐
25 tion in the specified output file
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27 <mode> Where <mode> is one of the seven available modes:
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29 • Union
30 A union is a set of features, which represent areas that
31 are in either of the operand layers.
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33 • Intersection
34 An intersection is a set of features, which represent the
35 common areas of two layers.
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37 • SymDifference
38 A symmetric difference is a set of features, which repre‐
39 sent areas that are in operand layers but which do not in‐
40 tersect.
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42 • Identity
43 The identity method identifies features in the input layer
44 with features in the method layer possibly splitting fea‐
45 tures into several features. By default the result layer
46 has attributes from both operand layers.
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48 • Update
49 The update method creates a layer, which add features into
50 the input layer from the method layer possibly cutting fea‐
51 tures in the input layer. By default the result layer has
52 attributes only from the input layer.
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54 • Clip
55 The clip method creates a layer, which has features from
56 the input layer clipped to the areas of the features in the
57 method layer. By default the result layer has attributes
58 of the input layer.
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60 • Erase
61 The erase method creates a layer, which has features from
62 the input layer whose areas are erased by the features in
63 the method layer. By default the result layer has at‐
64 tributes of the input layer.
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66 -input_ds <path>
67 Input data set path for the operation to be performed. For op‐
68 erations involving 2 datasets, this is one of the dataset.
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70 -input_lyr <name>
71 Layer name of the input_ds for which the operations have to be
72 performed ( Optional )
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74 -method_ds <path>
75 Method data set path for the operation to be performed. This is
76 usually the conditional data set supplied to the operation ( ex:
77 clip , erase , update ) This is the Second data set in the oper‐
78 ation ( ex : Union, Intersection , SymDifference )
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80 -method_lyr <name>
81 Layer name of the method_ds for which the operations have to be
82 performed ( Optional )
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84 -output_ds <path>
85 Output data set path for writing the result of the operations
86 performed by ogr_layer_algebra
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88 -output_lyr_name <name>
89 Layer name of the output_lyr_name where the output vector has to
90 be written. ( Optional )
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92 -overwrite
93 Indicates whether the output_ds have to be overwritten with the
94 generated result of ogr_layer_algebra
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96 -opt <NAME=VALUE>
97 Attributes for which the operation has to run on input_ds and
98 method_ds
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100 -f <format_name>
101 Select the output format.If not specified, the format is guessed
102 from the extension (previously was ESRI Shapefile). Use the
103 short format name
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105 -dsco <NAME=VALUE>
106 Dataset creation option (format specific)
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108 -lco <NAME=VALUE>
109 Layer creation option (format specific)
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111 -input_fields <NONE|ALL|fld1,fld2,fld3...>
112 Comma-delimited list of fields from input layer to copy to the
113 output layer , if eligible according to the operation
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115 -method_fields <NONE|ALL|fld1,fld2,fld3...>
116 Comma-delimited list of fields from method layer to copy to the
117 output layer , if eligible according to the operation
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119 -nlt <geom_type>
120 Define the geometry type for the created layer. One of NONE,
121 GEOMETRY, POINT, LINESTRING, POLYGON, GEOMETRYCOLLECTION, MULTI‐
122 POINT, MULTIPOLYGON, GEOMETRY25D, POINT25D, LINESTRING25D, POLY‐
123 GON25D, GEOMETRYCOLLECTION25D, MULTIPOINT25D, MULTIPOLYGON25D.
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125 -a_srs <srs_def>
126 Assign an output SRS, but without reprojecting
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128 The coordinate reference systems that can be passed are anything
129 supported by the OGRSpatialReference.SetFromUserInput() call,
130 which includes EPSG Projected, Geographic or Compound CRS (i.e.
131 EPSG:4296), a well known text (WKT) CRS definition, PROJ.4 dec‐
132 larations, or the name of a .prj file containing a WKT CRS defi‐
133 nition.
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136 1998-2023
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141 Oct 30, 2023 OGR_LAYER_ALGEBRA(1)