How can I get Estimate (text field) to roll up to parent issue via Project Automation Rule?

[Abe_Roba]

How can I get Estimate (text field) to roll up to parent issue via Project Automation Rule?  I can get it to work if it is a number field, but in our case since Estimate could be used interchangeably for time and cost, it was originally created as a text field.  I would like to add the values of the Estimate fields in the subtasks to roll up into the parent issue's Estimate field.  This is what I tried and it did not work:  {{subtasks.Estimate.join(" + ")}}

[Nic Brough -Adaptavist- · Accepted solution]

You can't "add up" text fields.  Computers are incredibly fast at processing, but they're dumb and can only do what they are told as it is explained to them.  If you use numbers, mathematics has some simple rules we can explain to them.  "Add four to five" makes sense. 

As your field is text rather than numbers, no, you can't.  What would the result of "add oogie to boogie" be?  A text field allows that as an input, so you can't expect it to be able to process it.   (Yes, there are expert systems that can read or listen and interpret correctly, but no-one is going to build them into a tracker just in case someone sets it up wrong)

[Abe_Roba]

Thanks for you witty, concise, and unambiguous response!

[Nic Brough -Adaptavist-]

I don't think I was witty - the "oogie to boogie" for example was trying to be light-hearted and it was mostly stolen from "Calvin and Hobbes"!

I think what I'd like to add is that you will need to dive into computer-think to be able to do this.  Somehow, you'll need to do something that turns your text into data that a computer can understand as being numeric so you can add it up.

[Abe_Roba]

Thanks Nic, I was able to find this method in the link below for Project Automation and successfully created a Rule to achieve this where I converted the Text field value to numeric and added it up to roll up from the subtasks to the parent and it worked!

https://support.atlassian.com/jira-software-cloud/docs/use-smart-values-to-manipulate-text-strings/