Changing Family Based on Parameter Value

[robertsb2010]

Hey everyone, I need some help. I have been trying to find a way to change a family type based on a parameter value and I am having trouble. In this script, I find the “specified supply airflow” and then divide it among all diffusers in a space. I’d like to give cfm ranges and automatically have the family change to the correct type based on what range it falls in. I was thinking the “if” node, but can’t seem to get it to function how I’d like. Any help is appreciated. I’ve attached the dynamo file and a screenshot.

Apply CFM across ATs.dyn (21.8 KB)

[Ewan_Opie]

If it is a numerical range or number you are using to define the inputs, then this may work for you.

[robertsb2010]

Thanks for the response! I’m going to try this out and see if it gets me where I want to be.

UPDATE: When I try this, it runs without error, but doesn’t change any families inside the revit file.

[Ewan_Opie]

I have shown Strings as inputs/outputs. Are you feeding actual family types into the inputs?

[robertsb2010]

That’s what I tried. That’s the end goal is to select actual families based on parameter values that are pulled from the revit file.

The entire script reads “specified supply airflow” of a space and divides that among all the diffusers it finds within a space. I would like to take the divided values and auto pick a family based on a given cfm range (i.e. select Family 1 if cfm is between 0-120 cfm, etc.)

Also, could you elaborate a little on what exactly that code block is doing? I get the general idea, but I’m a little inexperienced with code blocks.

[Ewan_Opie]

All good.
I am out of the office for a couple of days. I’ll get something on range input posted when I get back as I also have an idea on how to do this with OOTB nodes.

Unless there are any other ideas from the forum? Python gurus?

[Yna_Db]

@robertsb2010

what exactly that code block is doing?

That code block holds a conditional statement (similar function as an if node), see here:
http://dynamoprimer.com/en/07_Code-Block/7-3_shorthand.html

This conversation could also bring additional clues:

Replacing a number of selected elements with another family type keeping original dimensions

[Ewan_Opie]

Righto, I knew I had seen something like this before.

I’ve just typed this out on my phone but it should be able to be adapted for your purpose @robertsb2010

Example:

X=input list of values
a=family type 1 for values 0 to 100
b=family type 2 for values 101 to 200
c=family type 3 for values 201 to 300
d=family type 4 for values 3011 to 400

The code block contents:

x>=0&&x<=100 ?
a:
x>=101&&x<=200 ?
b:
x>=201&&x<=300 ?
c:
x>=301&&x<=400 ?
d:
"Out of range";

The inspiration:

If ( then , else) in dynamo

Konrad, Michael, Many thanks. Managed to make it work! And the code block processes a list of 100+ values in seconds, when some of the monstrosities I’ve built out of nodes took ages! Just goes to show the inherent inefficiency of visual programming I guess. The end result looks like this: [Capture3]                   Best Regards.

I’ll still see if my OOTB node solution idea works on Monday.

[Ewan_Opie]

Here is an example of the Code Block in action as well as my OOTB Node workflow.
Please let me know if this solves your problem @robertsb2010

Animation:

Screengrab:

[robertsb2010]

Wow, that code block is nice! I got it to work after toying with the code block contents a little bit. I was definitely confused by the code block workflow at first.

Also, I had to convert my list to ft3/sec as Dynamo doesn’t actually read cfm the way that Revit does. That wasn’t hard to do at all, just another step. Thanks for everyone’s replies!