# Region - Region agents (at least one required)¶

Every agent that participates in a Cyclus simulation represents either a facility, an institution or a region. Each region block defines an agent that acts as a region in the simulation. In contrast to the facility block that defines a prototype, this block defines an agent.

Each region block has the following sections in any order:

• name (required once) - a name for the prototype
• lifetime (optional once) - a non-negative integer indicating the number of time steps that this region agent will be active in the simulation
• config (required once) - the archetype-specific configuration
• institution (required at least once ) - an institution agent operating in this region

## Example¶

This example introduces two region agents. The first has the name MyHomeRegion, and is configured from the archetype with the name (or alias) NullRegion. The author of the NullRegion archetype has defined no archetype-specific data. The second has the name MyNeighborRegion and is based on the archetype with the name (or alias) GrowthRegion. The contents of the GrowthRegion section are defined by the author of the GrowthRegion archetype.

XML:

<region>
<name>MyHomeRegion</name>
<config> <NullRegion/> </config>
<institution>
... data for this institution goes here
</institution>
</region>

<region>
<name>MyNeighborRegion</name>
<config>
<GrowthRegion>
... archetype-specific input for a GrowthRegion archetype
</GrowthRegion>
</config>
<institution>
... data for this institution goes here
</institution>
</region>


JSON:

{
"region": [
{"name": "MyHomeRegion",
"config": { },
"institution": "... data for this institution goes here"}
},
{"name": "MyNeighborRegion",
"config": {"GrowthRegion": "... archetype-specific input for a GrowthRegion archetype"},
"institution": "... data for this institution goes here"}
]
}


Python:

{"region": [
{"name": "MyHomeRegion",
"config": { },
"institution": "... data for this institution goes here"},
},
{"name": "MyNeighborRegion",
"config": {"GrowthRegion": "... archetype-specific input for a GrowthRegion archetype"},
"institution": "... data for this institution goes here"},
],
}


## Grammar Definition¶

<element name="region"> <interleave>
<element name="name"> <text/> </element>
<optional>
<element name="lifetime"> <data type="nonNegativeInteger"/> </element>
</optional>

<element name="config">
<choice>
@Region_REFS@
</choice>
</element>

<oneOrMore>
<ref name="institution" />
</oneOrMore>

</interleave> </element>