Firth, or 1th, is a postfix calculator for fractions.

Firth is a stack based rpn calculator, created to be an improved version of Unix's dc. It supports basic arithmetic, a few forth primitives and is the perfect companion utility to Fractran.

Firth session with 6 MHz 286, 2.5MB RAM, DOS 5.0


The following example, will print the mixed fraction 3&1/6.

clr 11 4 div 5 12 div add mix

To print the decimal value of a fraction.

clr 22 7 div 1 791 div sub dec

To get the floor() of a fraction.

clr 17 4 div dup 1 mod sub .


Incoming: cccc forth