Tagnames as function arguments

If you use the tagname as an argument in one of the performance equation built-in functions, then the Performance Equation Scheduler evaluates the tagname according to the type of value expected by that particular function.

For example, if the function expects a tagname, then the performance equation passes a tagname to the function. If the function expects any other data type such as a string or a number, PE Scheduler gets the current value of the point and passes that to the function—as whatever data type is expected.

For example, the Concat function expects two or more strings as arguments. It concatenates all the arguments into a single string:

Concat('sinusoid', 'ba:level.1')

To evaluate this expression, the PE Scheduler takes the current value of the sinusoid point and the ba:level.1 point and passes these to the Concat function as strings. Concat then returns a string that is composed of the value of the sinusoid point followed by the value of the ba:level.1 point. If the current values of these points are, respectively, 85.329 and 30.478, Concat returns the following string:

85.32930.478