Validating Network Graphs

Note: Before you can validate network graphs, a network graph must first be constructed (see Connecting Network Graphs).

Network graph connection can be validated using a rule to check Network Attributes.

Network Attributes

Network Attribute	Description
max_reported_islands	Threshold for the number of isolated islands reported. If not set, default value of 1000 is used.
max_reported_positions	Threshold for the number of features reported in an island. If not set, default value of 1000 is used.
name	Name of the network graph (used when constructing the network graph using thename parameter of the add_position, remove_position, connect_positions and disconnect_positionsbuilt-in operations).
num_islands	Number of islands found in the network graph. A coherent network has one island which is equivalent to the whole network graph.
report_cutoff	Threshold for creating a report. If the number of nonconforming objects exceeds the report cutoff, no report is produced. If not set, default value of 1000 is used.

In the following example, a rule uses the num_islands network attribute to validate the network graph coherence. The name field is not applicable so has been left empty.

The expected result is that the network graph should only have one island.

Rule using the num_islands network attribute

Note: In network graphs with more than one island, the main island is considered to be the one which contains 50% or more of the objects queried.

Validation Results

Once created, network graph validation rules must be run using a Check Rules task (Check Rules Task), which will provide XML and HTML results (see Rule Conformance Results Report).

XML

The XML report lists each network using the connection_graph class for the <Object> tag.

Example XML report for network graph validation

HTML

Although rules are run against all network graphs, each is reported separately.

Note: The attributes num_islands and isolated_islands may not report all instances of islands and objects if they exceed reporting thresholds. See the data engineer who constructed your networks for details of the reporting thresholds set.

You can view the details of the isolated islands by clicking the objectlink for the network graph.

Viewing an island

For each island, the detail report shows all features and their attributes. In the example below, thepipe class has one FeatId attribute.

Viewing a network graph detail report