Component input to output branch length rules?

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Permalink Reply by David Rutten on February 20, 2013 at 1:20pm

The rules are quite complex and sometimes change per version, but there are two important reasons for the behaviour:

1. The ways datatrees change should be predictable per component. I.e. if you provide a single number the output should not differ fundamentally from when you provide two numbers as input.
2. A component should not destroy information stored in datatrees, as they are a sort of history record telling you where data came from.

The current logic is outlined in this document.

In short:

• If all inputs have item access and all outputs have item access then the datatree layout is copied from the master input parameter.
• If all inputs have list access and all outputs have list access, then the datatree layout is copied from the master input parameter.
• If some inputs have item while some outputs have list access, those outputs will have their trees grown by one layer.
• Input and outputs which have tree access are completely at the mercy of the component and their behaviour will differ on a per component basis.

--

David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Michael Pryor on February 20, 2013 at 1:59pm

Thanks a lot this really helped. The reason I ask is sometimes when making lengthy definitions my list can grow from say (0;0) to (0;0;0;0;0;0) which is fine, but when I package as a user object I want the output to be either (0;0) or (0;0;0) depending on as you say on inputs and outputs. So I wanted to be sure I was formatting correctly as simplify isn't the best solution in this situation. Thanks again.