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I don't understand task sequences


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Hi All,

Can you please help construct the appropriate task sequence numbers for the following task network?


More generally, is there an algorithm for creating task sequence numbers for a network defined by predecessors or successors? Either of the following tables fully represent the graph above, for example.


Without an automated approach task sequences will have limited applicability for the size/complexity of networks I am interested in modeling.



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I have tried to replicate what you are trying to do, the task sequences are quite powerful,. To automate you can link them to tables( I haven't done this yet, see the "Servers Using Task Sequence With Data Tables Flow Line" simbit!)

Everything is controlled through the sequence number:



Hope this helps, task sequences are great stuff!


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Here is a sequence numbering scheme to do the above task flow chart that you pasted. the task sequence numbering scheme that we support is very flexible and very friendly for defining a task sequence in a data table, and you can do as many nested task substreams as you like, but I agree that it can take a moment for how the numbering scheme works to click. At some point, agree it will be nice if we can provide a visual drawing tool to draw the sequence and the sequence numbers are entered automatically. But hopefully once you understand how to number your first flow diagram above, then won't be too difficult to do any of your other task flow charts that you have.

Task1 = 10

Task2 = 20.1

Task3 = 20.2

Task4 = 20.3

The above says do Task1 first, then do Task2 (task substream '1'), Task3 (task substream '2'), and Task4 (task substream '3') in parallel.

Task5 = 30.1.1

Task6 = 30.1.2

That says to do Task5 and Task6 when Task2 is finished. Basically, to do a nested task substream, a task numbered 30.1.2 is saying 'nested task substream '2' of task substream '1').

Task7 = 40 (you won't do this task until all tasks are finished - is the last task)

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The Resource Gantt is a good way to test the task sequences.

I added a resource (with logging turned on) for each task. I then assigned resources to their associated tasks in the task sequence.

I used the sequence numbers that Glenn suggested.

With the Gantt, you can verify the task sequence....




A slight downtime on the Task3 and Task4 resources does not impact the start time of Task5 and Task6, but it does impact the start time of Task7.




Give it a try!!!


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Adam, yep, the sequence numbers that Glen posted above will do that second flow diagram that you mentioned.

Task1 = 10

'Task1' must be finished first before any other task may be started because its primary number of '10' is smaller than any other primary number in the sequence.

Task2 = 20.1.1

Task3 = 20.1.2

Task4 = 20.2

Once 'Task1' is finished, you can start all of the tasks with primary numbers of '20' in parallel.

Task5 = 30.1.1

You can start 'Task5' once 'Task2' is finished, because it is a higher operation number of '30' that is on the same exact task substream. In other words you can do a 30.1.1 after 20.1.1 is finished.

Task6 = 30.1

You can start 'Task6' once 'Task2' and 'Task3' are finished. Because then you will have finished all the tasks with sequence numbers starting with '20.1' (finished all tasks with lower primary numbers that are part of the 'XX.1' substream including any nested substreams).

Task7 = 40

This task has the highest primary number so can be started once all other tasks have finished.


As I said in my first post, the task sequencing number scheme that we provide is very flexible and should be able to handle any flow diagram that you come up with. And the approach is particularly friendly if tasks are being defined using a table data approach. Some time down the road, hopefully we'll get a chance to provide a visual flow chart editor that just auto-enters task sequence numbers in for you. Until then, once you get the hang of how the numbering scheme works with a few examples, hopefully not too difficult to pick up. I think the basic rules of the task sequence numbering scheme are also described in the help documentation.

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  • 3 weeks later...

Adam, just a note that for a task sequence, based on your feedback on the Forum we have prioritized an enhancement that will allow you to use either the sequence numbering scheme that we currently support or an 'Immediate Predecessors' field to define task precedence. For your network diagrams, seems like you will be more comfortable going with the Immediate Predecessors field approach and for each task just listing out the predecessor numbers.

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