Create Cartographic Partitions

Summary

Creates a mesh of polygon features that cover the input feature class in which each output polygon encloses no more than a specified number of input features or input vertices. as determined by the density and distribution of the input features.

The resulting partition feature class is ideally suited for the Cartographic Partitions geoprocessing environment setting. The Cartographic Partitions environment setting causes certain geoprocessing tools to load and process input features by partition. These tools operate contextually, meaning that multiple features, possibly from multiple themes, must be loaded simultaneously. Memory limitations are encountered with large datasets. Partitioning allows large datasets to be processed by these tools in portions sequentially.

Illustration

Smaller partition polygon features are created where there is a higher density of road features.

Usage

• This tool creates a polygon feature class designed to be used in the Cartographic Partitions geoprocessing environment setting. Tools that honor this environment setting process input features in portions defined by the partition polygons to avoid exceeding memory limitations. The following tools honor the Cartographic Partitions environment setting:

  • The Aggregate Polygons tool
  • The Collapse Road Detail tool
  • The Delineate Built-Up Areas tool
  • The Detect Graphic Conflict tool
  • The Merge Divided Roads tool
  • The Resolve Building Conflicts tool
  • The Resolve Road Conflicts tool
  • The Simplify Building tool
  • The Simplify Line tool
  • The Simplify Polygon tool
  • The Smooth Line tool
  • The Smooth Polygon tool
  • The Thin Road Network tool

• Input features should correspond to the features that you intend to process together for multiscale display. For example, if you intend to use the Thin Road Network tool to process a feature class containing streets together with another containing highways, enter both of these as inputs to the Create Cartographic Partitions tool to create partitions that are relevant to the distribution and density of both datasets considered together.

Syntax

arcpy.cartography.CreateCartographicPartitions(in_features, out_features, feature_count, {partition_method})

Parameter	Explanation	Data Type
in_features [in_features,...]	The input feature classes or layers with feature distribution and density, or vertex distribution and density, that determine the size and arrangement of output polygons. The input features are typically destined for subsequent processing with contextual generalization or conflict resolution geoprocessing tools. Typically, the input features, when considered simultaneously, would exceed memory limitations of generalization or conflict-resolution geoprocessing tools, so partitions are created to subdivide inputs for processing.	Feature Layer
out_features	The output polygon feature class of partitions each of which encloses a manageable number of input features or manageable number of input vertices not exceeding the number specified by the feature_count parameter.	Feature Class
feature_count	The ideal number of features or vertices (depending on the partition_method parameter value) to be enclosed by each polygon in the output feature class. The recommended count for features is 50,000, which is the default value. For vertices, 1 million vertices will consume approximately 0.5 GB of memory depending on the tool using the partitions. The feature count cannot be less than 500.	Long
partition_method (Optional)	Specifies whether the feature_count parameter references the ideal number of features or the ideal number of vertices in each output polygon. FEATURES —Partitioning considers the number and density of individual features. This method is applicable in most cases and is the default. VERTICES —Partitioning considers the number and density of vertices. This method is used in cases in which the input data contains a relatively small number of very complex features, such as high-resolution country polygons, or when very long features are likely to cross multiple partition boundaries, such as contour lines.	String

Code sample

CreateCartographicPartitions example (Python window)

The following Python window script demonstrates how to use the CreateCartographicPartitions function in immediate mode.

import arcpy
arcpy.env.workspace = "C:/data/cartography.gdb/transportation"
arcpy.CreateCartographicPartitions_cartography("roads.lyr", "partitions", 50000, "FEATURES")

Environments

• Output Coordinate System

Licensing information

• Basic: No
• Standard: No
• Advanced: Yes