Hi! I have an app that displays data as follows:
Both columns look like lists of numbers but the format is text that has been written to a spreadsheet when data was archived (this is part of a record of app usage).
I would like to write an expression that compares the set of numbers in “D to W session in which ‘GOT IT’ was tapped” with those in “D to W sessions in which a mistake was made” and writes the following to a column in the spreadsheet as text:
<em>1368</em>, 1369, 1370, 1371, 1375, 1383, 1399, <em>1432</em>, 1445, <em>1465</em>, 1478, 1498, 1531
That would allow me to take advantage of the new rich text formatting capability in order to emphasize the sessions in which a mistake was made:
[Rich Text Formatting - in Preview Program](https://community.appsheet.com/t/rich-text-formatting-in-preview-program/52714) Announcements
The following feature has been added to the Preview Program. Feel free to try out the feature and report issues or possible improvements in this thread. AppSheet is expanding how text can be formatted. For data that is typed as LongText, app creators can now choose to render Markdown or HTML in Detail views. Note: In all views other than Detail, the value will render as plain text. How do app creators use the feature? Start with data that has HTML or Markdown inputs. In this example, th…
One difficulty is that the number of items in the top column can be between 6 and about 23 or so and the number of items in lower column can be between 0 and about 10 or so.
I imagine that, if this is possible, it would be a pretty complicated expression but it only needs to be written once for each record and that writing task doesn’t come up that often so, even if the expression is a little expensive, I think that would be OK.
Thanks for your attention!
P.S. The only approach that comes to mind is 10 nested SUBSTITUTE() expressions. That would probably require lots of IF() expressions to prevent errors and SPLIT() and INDEX() expressions to chop the strings up so that their parts can be compared. Is that what is required?

