Geotrace, area() calculation, string length

It has been posted before, but no matter where I look I can not find a quick and easy solution!

Problem summary:

a) ODK aggregate constrains string length on geotrace or geoshape submissions, whereas Kobo toolbox does not.
b) Kobo toolbox can not accept or publish forms with area() calculation, whereas this is no problem on aggregate
c) Kobo collect and ODK collect are both perfectly capable of calculating area(), if this calculation is in a form uploaded to aggregate

Result: I have to choose between collecting the area of a shape, but in so doing lose all the geodata (perimeter of shape) - OR - saving all the geodata, but having to add an extra stage to the data processing side to be able to then calculate area from the string of geotrace, and then insert the area into a new column in the final data sheet.

Surely there is a way to effortlessly resolve this problem? Is there an easy solution (without having to edit the XML document) to remove the limitation on string length for geotrace data using ODK collect/aggregate? Or a solution to enable area() calculation using Kobo toolbox?



Fields in Aggregate are limited to 255 characters. You can use the bind::odk:length column in an XLSForm to specify a larger maximum length for specific fields. I don't think this is documented currently for some reason but here is an issue with the information:

Perfect! Thank you LN!

That is the quick and easy solution I was looking for. I had seen how to add the bind to the xml document, but the simple instruction for adding it to the XLSForm remained elusive. This really should be in the documentation somewhere!

Now my form works perfectly :slight_smile:

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I'm getting error using bind::odk:length for geotrace -- The prefix "odk" for attribute "odk:length" associated with an element type "bind" is not bound.

What could be the reason??

Could you attach a sample form? I could take a look there.

sampleyouthfarmmapprog.xlsx (32.9 KB)
Please find sample forms attached. Thanks for your support @Grzesiek2010

And when exactly do you get this error? Wile converting, opening the form, working with the form?

While converting @Grzesiek2010 .

Another question is does Aggregate give room for geotrace characters more than 255??

I downloaded the form you attached and there is no problem with converting. I used what about you?

Thanks @Grzesiek2010. It works on xls form online. I was using the offline xls converter.

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