We have a lot of data in UI tables, so I wanted to write code that extracted the cell values to a ROWSxCOLUMNS matrix, that I could reuse in each test.
Did you try custom commands? I have some for more basic stuff like 'get data-value attribute for the element with data-name attribute of x' which I can use in any test.
That said, I find checking for specific values in the page against other page values to be really difficult so if you're doing that with the table... good luck!
if that functionality isn't already present in the UI, e.g. by selecting a filter or exporting, then perhaps it belongs in the domain of a scraper rather than a testing tool
And... I just couldn't figure out a way!