I'm not an engineer anymore, but at one point I was doing a lot of structural analysis in Excel. When we found the existing spreadsheets (purchased) weren't goo

I'm not an engineer anymore, but at one point I was doing a lot of structural analysis in Excel. When we found the existing spreadsheets (purchased) weren't good enough, I wrote an entire library of analysis and design spreadsheets, the most complex being for the design of reinforced concrete columns: hundreds of lines of VBA, and only lots of recursion could crack this stuff without support for symbolic calculus. This is pretty common practice, in Australia at least.