Boolean Logic in Branch Choice

[Andres Collart]

Hi Harry,

I'm trying to set up a model where I need to use boolean logic in the branch choice to help direct entities. However, nothing has worked thus far. 

I want to route things based on simulation time as shown below

([Generator1].SimTime < 17h)*1+([Generator1].SimTime >=17h)*2

Thanks,

Andres

[Harry King]

Andres,

Two changes are needed:

1) enclose the whole expression in single quotes (because it includes spaces)

2) enclose the unit h in square brackets (because a unit is an object)

Your final expression will be:

     '([Generator1].SimTime < 17[h])*1+([Generator1].SimTime >=17[h])*2'

You can write this expression more clearly using the ternary operator:

     '[Generator1].SimTime < 17[h] ? 1 : 2'

Also, every entity has the output SimTime, including the Branch object, so you can write the expression as:

     'this.SimTime < 17[h] ? 1 : 2'

Harry

[Andres Collart]

Harry,

Thank you, that worked perfectly!

-Andres

[Andres Collart]

Hi Harry,

I'm running into a similar issue with some Thresholds. I have an entity generator that I want to operate if a certain Queue Length is <5. I tried using the OperatingThresholdList within the generator object but that didn't seem to work with the below expression. Given that I created a SignalThreshold object and a Signal, I'm trying to set the Signal.NewState input to the below expression too but it isn't taking it because it "expects a boolean value". Any idea how do this?

'[TruckGenQueue].QueueLength > 5 ? False: True'


Thank you,

Andres

[Harry King]

Andres,

You cannot use the names True and False in an expression. Use their numerical equivalents: 1 for TRUE and 0 for FALSE.

In any case, you can simplify your expression by writing it as the following:

     '[TruckGenQueue].QueueLength <= 5'

There is no need to use the ternary operator (?) in this case because the comparison already provides a boolean value.

Lastly, the NewState keyword for EntitySignal does not accept an expression. It would be better to use an ExpressionThreshold for this purpose, as you had originally intended.

Harry

[Andres Collart]

Harry,

Worked perfectly as an ExpressionThreshold, thanks!

-Andres