Scientific RPN Calculator (with ATTINY85)

[Paul Dale]

Gamma first appeared on the HP-34C and I believe it is present on most subsequent models. It is disguised as x!. Models without call it n!. For small arguments, the usual approach is to make them large using the recurrence relationship. Negative arguments require the reflection formula but this could be left out.

Take care with the edge cases with h/h.ms, they can be tricky.


Pauli