I mentioned previously that I recently bought a TI Nspire CX CAS. Today I thought I’d have a go at backing up the small programs I’d written using the tilp2 package in Ubuntu since I use Linux and there is no official TI support for that. This worked, sorta, but you end up with programs in a proprietary binary format that nothing can read (and you don’t really want to put into version control).

While in a failed attempt to find a useful conversion tool, I discovered that TI produce Nspire CAS and Nspire apps for iPad, each costing £22 on the iTunes store (I’m not clear why you’d choose to buy the less fully featured non-CAS version since they are the same price).

So I took the plunge and it turns out you can transfer files into the iPad app through Dropbox or e-mail and voila, I can run my programs on my iPad. Here for example is a screenshot of the naïve implementation of our general Pi example, written on my calculator and run on my iPad.

And my improved version which uses the sum rather than a loop.

So this is very cool. It’s a bit embarrassing since I’ve spent the last few weeks knocking the programmability of the iPad, it’s much faster than my calculator (but not as cool!), and cheaper. And I’ve still not found a way to put the code into git.