Label | Explanation | Data Type |
Input Above Features | The input line feature layer containing lines that intersect—and will be symbolized as passing above—lines in the Input Below Features parameter. | Layer |
Input Below Features | The input line feature layer that intersects—and will be symbolized as passing below—lines in the Input Above Features parameter. These features will be masked by the polygons created in the Output Underpass Feature Class parameter. | Layer |
Margin Along |
Sets the length of the mask polygons along the Input Above Features parameter by specifying the distance in page units that the mask should extend beyond the width of the stroke symbol of the Input Below Features parameter. The Margin Along parameter must be specified, and it must be greater than or equal to zero. Choose a page unit for the margin; the default is points. | Linear Unit |
Margin Across |
Sets the width of the mask polygons across the Input Above Features parameter by specifying the distance in page units that the mask should extend beyond the width of the stroke symbol of the Input Below Features parameter. The Margin Across parameter must be specified, and it must be greater than or equal to zero. Choose a page unit for the margin; the default is points. | Linear Unit |
Output Underpass Feature Class |
The output feature class that will be created to store polygons to mask the Input Below Features parameter. | Feature Class |
Output Mask Relationship Class |
The output relationship class that will be created to store links between underpass mask polygons and the lines of the Input Below Features parameter. | Relationship Class |
Expression (Optional) | An SQL expression used to select a subset of features in the Input Above Features parameter. Use quotation marks—for example, "MY_FIELD"—or if you're querying personal geodatabases, enclose fields in square brackets—for example, [MY_FIELD]. See SQL reference for query expressions used in ArcGIS for more information on SQL syntax. | SQL Expression |
Output Decoration Feature Class (Optional) | The output line feature class that will be created to store parapet features. | Feature Class |
Wing Type (Optional) | Specifies the wing style of the parapet features.
| String |
Wing Tick Length (Optional) | The length of the parapet wings in page units. The length must be greater than or equal to zero; the default length is 1. Choose a page unit (points, millimeters, and so on) for the length; the default is points. This parameter does not apply to the Wing Type value of NONE. | Linear Unit |
Summary
Creates bridge parapets and polygon masks at line intersections to indicate underpasses.
Illustration
Usage
Intersecting symbolized line features as inputs are required.
This tool is identical to the Create Overpass tool except that the Expression parameter selects from the Input Below Features parameter in this tool as well as from the Input Above Features parameter in the Create Overpass tool.
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The Input Above Features layer can be the same as the Input Below Features layer in the case of self-overlapping features. When Input Above Features and Input Below Features layers are the same, an SQL expression is required for further refinement of feature selection.
Parameters
arcpy.cartography.CreateUnderpass(in_above_features, in_below_features, margin_along, margin_across, out_underpass_feature_class, out_mask_relationship_class, {where_clause}, {out_decoration_feature_class}, {wing_type}, {wing_tick_length})
Name | Explanation | Data Type |
in_above_features | The input line feature layer containing lines that intersect—and will be symbolized as passing above—lines in the Input Below Features parameter. | Layer |
in_below_features | The input line feature layer that intersects—and will be symbolized as passing below—lines in the Input Above Features parameter. These features will be masked by the polygons created in the Output Underpass Feature Class parameter. | Layer |
margin_along |
Sets the length of the mask polygons along the Input Above Features parameter by specifying the distance in page units that the mask should extend beyond the width of the stroke symbol of the Input Below Features parameter. The Margin Along parameter must be specified, and it must be greater than or equal to zero. Choose a page unit for the margin; the default is points. | Linear Unit |
margin_across |
Sets the width of the mask polygons across the Input Above Features parameter by specifying the distance in page units that the mask should extend beyond the width of the stroke symbol of the Input Below Features parameter. The Margin Across parameter must be specified, and it must be greater than or equal to zero. Choose a page unit for the margin; the default is points. | Linear Unit |
out_underpass_feature_class |
The output feature class that will be created to store polygons to mask the Input Below Features parameter. | Feature Class |
out_mask_relationship_class |
The output relationship class that will be created to store links between underpass mask polygons and the lines of the Input Below Features parameter. | Relationship Class |
where_clause (Optional) | An SQL expression used to select a subset of features in the Input Above Features parameter. Use quotation marks—for example, "MY_FIELD"—or if you're querying personal geodatabases, enclose fields in square brackets—for example, [MY_FIELD]. See SQL reference for query expressions used in ArcGIS for more information on SQL syntax. | SQL Expression |
out_decoration_feature_class (Optional) | The output line feature class that will be created to store parapet features. | Feature Class |
wing_type (Optional) | Specifies the wing style of the parapet features.
| String |
wing_tick_length (Optional) | The length of the parapet wings in page units. The length must be greater than or equal to zero; the default length is 1. Choose a page unit (points, millimeters, and so on) for the length; the default is points. This parameter does not apply to the Wing Type value of NONE. | Linear Unit |
Code sample
The following Python window script demonstrates how to use the CreateUnderpass function in immediate mode.
import arcpy
arcpy.env.workspace = "C:\data"
arcpy.env.referenceScale = "50000"
arcpy.CreateUnderpass_cartography("roads.lyr", "railroads.lyr", "2 Points", "1 Points",
"cartography.gdb/transportation/under_mask_fc",
"cartography.gdb/transportation/under_mask_rc", "'RelationshipToSurface' = 3",
"cartography.gdb/transportation/tunnel", "PARALLEL", "1 Points")
This stand-alone script shows an example of using the CreateUnderpass function.
# Name: CreateUnderpass_standalone_script.py
# Description: creates a mask where one feature
# is visually below another feature
# Import system modules
import arcpy
from arcpy import env
# Set environment settings
env.workspace = "C:/data"
env.referenceScale = "50000"
# Set local variables
in_above_features = "roads.lyr"
in_below_features = "railroads.lyr"
margin_along = "2 Points"
margin_across = "1 Points"
out_overpass_feature_class = "cartography.gdb/trans/under_mask_fc"
out_mask_relationship_class = "cartography.gdb/trans/under_mask_rc"
where_clause = "'RelationshipToSurface' = 3"
out_decoration_feature_class = "cartography.gdb/trans/tunnel"
wing_type = "PARALLEL"
wing_tick_length = "1 Points"
# Execute Create Underpass
arcpy.CreateUnderpass_cartography(in_above_features,
in_below_features,
margin_along,
margin_across,
out_overpass_feature_class,
out_mask_relationship_class,
where_clause,
out_decoration_feature_class,
wing_type,
wing_tick_length)
Environments
Licensing information
- Basic: No
- Standard: No
- Advanced: Yes