question

sara S2 asked Jul 22 2020 at 3:46 PM sara S2 commented Jul 29 2020 at 5:53 PM

How to set the condition "a list is empty" in decide activity?

Hello,

How to set the condition "a list is empty" in decide activity?

(FlexSim version 19.0.0)

Regards.

Software Version:

Other

Software Version:

Other (please specify)

process flow decide activity

· 2

Jordan Johnson answered Jul 22 2020 at 3:52 PM tannerp commented Jul 24 2020 at 7:19 PM

It would be easier to you a pull from list activity. Check the "use max wait timer" box. In the max wait timer, choose No Wait for the amount of time, and when it fires, send the token to connector 2.

What this means is that the token will do a test pull. If there are items on the list, the the pull succeeds, and the token will go out connector 1. If you don't want to remove the items from the list, just check the "leave items on list" box. If there are no items on the list, the max wait timer will fire, and send the token out connector 2.

· 14

sara S2 commented · Jul 22 2020 at 6:01 PM

@jordan.johnson, thank you for the reply.

I need to use a "Decide" activity in the process flow. Is there an expression to use for list like for the model objects (for example: Model.find("Queue").subnodes.length == 0)? If not, would you please explain the solution you recommend with figures because I didn't understand exactly how this should be.

0 ·

tannerp sara S2 commented · Jul 22 2020 at 6:08 PM

You can check the box for "Use Max Wait Timer" and then release the token to connector 2 if the wait timer goes off (fails). I set up an example model that only has one item on the list. The first token pulls the item, then the second token fails and is sent to a different connector, similar to a Decide activity.

Hope this helps!

list max wait timer.fsm

1 ·

use-max-timer-list.png (8.4 KiB)

list-max-wait-timer.fsm (20.8 KiB)

sara S2 tannerp commented · Jul 22 2020 at 8:04 PM

@tanner.p, thank you for your help.

1 ·

Show more comments

sara S2 commented · Jul 22 2020 at 8:04 PM

@jordan.johnson, thank you for your help.

0 ·