Zogna is a calculator for NDS.

It supports:

1.Support “+ – * / ^ % ( )”
2.Support “sin cos tan” ,input is angle ,EXample: sin60
3.Support “asin acos atan” ,ouput is angle,example: asin0.5
4.Support “exp sqrt log ln”,example: ln2
5.Support “negative number”,flag:’f’,example:’-3.5′,as ‘f3.5’
6.Support syntax highlighting
7.Support pi=3.141593 e=2.718281
8.Support a^b as pow(a,b), a%b as mod(a,b)
and more…

http://code.google.com/p/zognc/