(12C) Decimal to Fraction

[Joe Horn]

My DEC2FRAC program on Goodies Disk #3 (21 March 1991) for the HP 48 uses this algorithm: "Continued Fractions by fast recursion formula, then make a single calculated jump backwards to the best possible fraction before the specified maximum denominator." It gets the best possible answer even if it's NOT one of the principal convergents of the continued fraction, and does so very quickly. The RPL listing (linked above) is fully commented. Porting it to the HP-12C is left as an exercise for people with more patience with the 12C than I have.