CalcNode

An invisible widget which can perform a calculation on a set of input PVs and provides the output as a PV local to the screen.

Since different UI tools use different syntax to configure their equivalent calc tools, the calculation attribute here should be written as a general python statement. The supported operators are bitwise, negation, comparators, basic math, exponents, and boolean operations.

• Special Attributes

Name	Type	Description
pv	String	The name used to reference the output values
A	String	Input PV, the value of which can be referenced as A in the calculation
B	String	Input PV, the value of which can be referenced as B in the calculation
C	String	Input PV, the value of which can be referenced as C in the calculation
D	String	Input PV, the value of which can be referenced as D in the calculation
calc	String	The calculation to perform, provided in python syntax

• Example

# If the motor reports having GAIN_SUPPORT, show enable/disable LED
EnableCalc: !Calc
        A:    "{motor-pv}.MSTA"
        calc: "(A&2048)==2048"
        pv:   "{motor-pv}:TorqueDisplay"
        
EnableLED: !VStretch:Group
        visibility: "{motor-pv}:TorqueDisplay"
        children:
                - !VCenter:Group
                        children:
                                - !Apply:OnOffLED
                                        size: "{on-off-width}"
                                        control-pv: "{motor-pv}.CNEN"