Elon Musk just tweeted buy MPIR! I’m kidding, but I’m keeping my eye on the stock price tomorrow. 🙂

I scratched an itch I’ve had for a long time to allow big integer calculations in Excel. The main issue was building MPIR on Windows. Only add, mul, and sub so far. One issue was converting strings to and from the underlying C data types. The MPIR library uses char* for the string representation but Excel limits those to 255 characters. The workaround is to use a range of strings.

There is always the issue of modifying handles in memory or allocating new handles. My current thinking is using MPZ.MUL(z1, z2) for in memory updating of z1 and \MPZ.MUL(z1,z2) for returning a new handle.