Need Help On Expression Binding

({Root Container.PIDProcessVal::ProcessHiVal})-({Root Container.PIDProcessVal::ProcessLoVal})/5

error msg appear “caused by ExpressionException: Expression left operand is null.”

need to perform calculation using parameter value please suggest how to perform.

Are you sure about the double : ? ({Root Container.PIDProcessVal :: ProcessHiVal})
I suppose “ProcessHiVal” and “ProcessLoVal” are custom properties, right?
In this case the line should be {Root Container.PIDProcessVal.ProcessHiVal}-{Root Container.PIDProcessVal.ProcessLoVal}/5.
Also, you know that your expression ( as you wrote it ) will do ProcessHiVal - the result of ProcessLoVal / 5, right?

hi bertulli thanks for your reply, tried with syntax you have provided butfollowing error msg is coming
Unable to find component for path: ‘Root Container.PIDProcessVal.ProcessHiVal’

im using custom properties mapped with UDT i need to use that tag for calculation kindly suggest better way if you have any. i am using this calculation for Major Tick Span calculation. (im calculating difference between max and min value and divide by 5 )

Are you using a “Numeric Text Field” named “PIDProcessVal” with two custom properties named “ProcessHiVal” and “ProcessLoVal”?
What component are you using for “calculation for Major Tick Span calculation”?

PIDProcessVal is UDT (Datatype) defined tag.
ProcessHiVal and ProcessLoVAL are tags in that UDT
im passing the value to a POPUP where im using the Linear Scale i need to dynamically calculate the Major Tick Span for that POPUP.

Ok, now I understand what you are trying to achieve.
Check this documentation, it should help you out :wink: https://docs.inductiveautomation.com/display/DOC79/Parameterized+Popup+Window+and+UDTs

thanks Bertulli. pls share link if have any user manual for component binding in details

Well this -> https://docs.inductiveautomation.com/ is the Ignition’s Manual link.
If you want something in details, in this case “binding”, you can search it inside the “Search” text field.