Does Not support Factorial

[Former user]

Originally reported on Google Code with ID 24

What steps will reproduce the problem?
1.  ender 3! 

What is the expected output? What do you see instead?

the result of 3! should be 3*2*1 = 6

What version of the product are you using? On what operating system?

.7 

Please provide any additional information below.

Reported by dennis.schaaf on 2007-02-13 08:54:21

[Former user]

``` I'm missing that function, too. It is widely used in statistics, but crops up in other areas as well. And, just to catch up with the default MS Windows calculator, it would be nice to have the factorial for non-integers on my favorite calculator as well.

Given the usual definition n! = n*(n-1)*...2*1, something like "0.37!" looks odd on first sight. But mathematicians found out, that factorials can be interpolated in a "nice and decent" way. The MS calculator returns these "nice" values.

Should you decide to implement this function, feel free to contact me. I am able to help out with the mathematics. For instance, 0.37! is "roughly" 0.889313507429101701928688000953917586655876997735163541862664701290421764983186341346, a value that bc evaluated within 0.15 seconds, after I fed it with my factorial script.

```

Reported by `[e-mail]` on 2007-04-16 01:14:56

[Former user]

``` The svn version already has preliminary support for factorial, but it can't compute 0.37! yet.

Would you kindly share your bc script to calculate the factorial? ```

Reported by `ariya.hidayat` on 2007-04-16 08:47:39 - Status changed: `Started` - Labels added: Type-Enhancement, Milestone-0.8 - Labels removed: Type-Defect

[Former user]

``` OK, who shall I send the file to?

Wolf ```

Reported by `[e-mail]` on 2007-04-17 23:52:55

[Former user]

``` Please send it to me: [e-mail]

Thank you in advance ! ```

Reported by `ariya.hidayat` on 2007-04-18 14:53:29

[Former user]

Reported by `helder.pereira.correia` on 2007-05-11 23:10:24

[Former user]

``` Maybe we should consider expressions like "sin(3)!" to be recognized. Or maybe just the ones like "(sin(3))!". ```

Reported by `helder.pereira.correia` on 2007-05-11 23:14:32

[Former user]

Reported by `helder.pereira.correia` on 2007-07-02 08:40:13 - Status changed: `Fixed`