Dear Phil
thanks so much for your response. Indeed I'll been looking and there is no such Excel function in XLSForm.
What I want to achieve is quite simple but I cannot get around to create the xlsform syntax in Survey123 Connect.
I have two (field) set of data (column), Area in ha and Dry matter in kg.
This How sumproduct work in Excel I would like to achieve the same but with some additional. please see image below with an example of my data.
How can it make this work in Survey123?, the data field name is Area_ha and Dry_matter, this data is entered by the field surveyors. In the diagram I show how the function should work behind the scene, the end result show be 1077.33
Any ideas or suggestions are welcome.
Thanks in advance.
Cheers,
Federico