Conditional Filtering is where the decision about which features are output to which connection is decided by some form of user-defined test or condition. The Tester is the prime example of this, but there are many other transformers for conditional filtering.
Because of this varied selection - and because of some excellent updates in FME 2013-SP1 - I’m going to try and explain which transformer to use and when.
Mapping FME Feature Types (layers) is greatly complicated when there is no direct correlation between the source and destination schemas. Hundreds of tests and connections can result in a workspace worthy of the “FME Chamber of Horrors”. The SchemaMapper transformer can help by testing the features against mappings defined in a lookup table. Or, as Kenny Rogers might say, “I just dropped a SchemaMapper in, to see what condition my Attr Value Field was in”.
As Spiderman once said, with great power comes great responsibility; and FME’s SchemaMapper transformer certainly has such powers and definitely needs a responsible user. In previous SchemaMapper posts I showed simple Feature Type and attribute mappings. Now it’s time to take your SchemaMapper use to the next level with conditional schema mapping.
The SchemaMapper transformer is - rightly or wrongly - infamous for its complexity. But in a previous SchemaMapper post I showed how simple it was for mapping attributes from one name to another, and now I’ll demonstrate basic techniques for mapping Feature Types.
Contents:
Anatomy of an FME Project: Parts III and IV
Measure Generation from Z Values
Shutdown Scripts and Logged Features
Updated Transformer Help
Drag and Insert Updates
This edition of the FME Evangelist is back to a general mix, with a good example of generating measures, a useful new TCL/Python function, and a sneak peak of a new Transformer Help document; not forgetting the ongoing anatomy of an FME project.