Hi,
The BulkAttributeRenamer can be used effectively.
1) BulkAttributeRenamer
Rename: Selected Attributes
Seleted Attributes: Number
Action: Regular Expression Replace
Text To Fine: .*
String: Type (Attribute Value)
2) AttributeExposer
Attributes to Expose: Type A, Type B, Type C
3) Aggregator
Group By: Town
Mode: Attributes Only
Keep Input Attributes: No
Attributes to Sum: Type A, Type B, Type C
4) AttributeCreator
Sum = @Value(Type A)+@Value(Type B)+@Value(Type c)
Takashi
I found that attribute value can be specified as new attribute name in the AttributeCreator of FME 2014. If you are using FME 2014, can use the new functionality.
1) AttributeCreator
@Value(Type) = Number (Set value of "Type" to new attribute name)
Sum = Number
2) AttributeExposer
Attributes to Expose: Type A, Type B, Type C
3) Aggregator
Group By: Town
Mode: Attributes Only
Keep Input Attributes: No
Attributes to Sum: Sum, Type A, Type B, Type C
Sorry, that's not new. FME 2012, 2013 also can do that. You can type "@Value(Type)" directly in Attribute Name column of the AttributeCreator.