During my research of a ATM theory of relativity, I happen to come across a wonderful little tool. It is a PC calculator that is accurate to 80sf and I have found it very useful checking my less accurate math programme.
It is completely free and has only to be downloaded to your PC. I can recommend it to any of you that work with mathematics.
The site where you can download the Console calculator is http://ccalc.shanebweb.com/
I hope it is of use to some of you.