HP 12C can't do decimal factorial

[Dieter]

(10-18-2017 03:18 PM)Gamo Wrote:  HP 12C return decimal factorial to Error#0
HP 15C able to do this for example 0.5! = 0.886227

Sure. The 12C calculates the factorial – which is defined for non-negative integer arguments. So just like on the HP41, HP67 and many other HPs everything else throws an error. Which is perfectly correct.

The 34C, 15C, 35s and some other HPs do not calculate x! but actually Γ(x+1). Which for integer arguments is the same as x!. So if you want to calculate Γ(1,5) = ½√π = 0,886... you can do so by evaluating 0,5! on these special calculators.

BTW take a look at the keyboard of the 12C and 15C. On the 15C the key label is "x!" while on the 12C it's "n!" – since the argument has to be a natural number.

(10-18-2017 03:18 PM)Gamo Wrote:  Is there any work around to do this on HP 12C ?

No. The 12C has no Gamma function.

Dieter