Bind object property to multiple parameters?

Hi,

I’m trying to bind the liquidColor property of the cylindrical tank to 2 or more parameters in Perspective. For example if the “Hi” parameter is true to use orange, if “HiHi” is true use red, if “Lo” is true use yellow etc.

I tried multiple “If” statements, but adding the second statement causes an error. Case/switch wouldn’t work because it compares the value of a single parameter.

Thank you,
Ali

Assuming your Hi, HiHi and Lo are bool’s, use binEnc() to combine them. It will return an int, that can be used in a case statement.

case(binEnc(tag1,tag2,tag3),
     0,"all false",
     1,"1,0,0",
     2,"0,1,0",
     4,"0,0,1",
    "default")

I believe you can also use the style to set the color based on the number returned from the binEnc().

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You should use the Expression Structure binding. This allows you to bind multiple values into the Expression object. I always recommend including a transform after the Expression structure, like so (you could also use an expression structure if you prefer):

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That’s clever. Thank you.[quote=“bpreston, post:2, topic:43327, full:true”]
Assuming your Hi, HiHi and Lo are bool’s, use binEnc() to combine them. It will return an int, that can be used in a case statement.

case(binEnc(tag1,tag2,tag3),
     0,"all false",
     1,"1,0,0",
     2,"0,1,0",
     4,"0,0,1",
    "default")

I believe you can also use the style to set the color based on the number returned from the binEnc().
[/quote]

So this can be used to assign the values of 2 parameters to 2 variables. How can I use these variables to return a string for the color?

Let’s say I bind variable ‘a’ to the ‘Hi’ param and ‘b’ to ‘HiHi’. I end up with 2 boolean variables that match the boolean parameters. I need the output to be a string based on the state of the parameters/variables. This string would set the liquidColor property of the cylindrical tank. What is the operator I would need to evaluate these 2 (or more) variables and map to a string?

Thanks,
Ali

That’s what you use the transform for. You can specify any logic and return you’d like in the transform, so you could do something like

color = '#FFFF00'. # default to yellow, or you can wrap this in logic.
if value['a']:
    color =  '#FFA500'  # if "Hi", then use orange
if value['b']:
    color = '#FF0000'  # if "HiHi" then use red
return color
1 Like