Talk:Factorial

From Rosetta Code

range limits for the factorial function[edit]

Just a thought...it would be interesting to programmatically identify the range limits of the factorial function for the unknown implementation. (The C and c++ implementations, for example, will overflow at different places depending on the range of int.) --Short Circuit 18:33, 30 January 2009 (UTC)

Yes, for non-native speakers of any language, it would be nice to know how big the thingys are: int, short, long, long long, etc. For experienced programmers, I imagine this is old hat, but to programmers who can barely spell C, ... not so obvious. --- Gerard Schildberger 21:35, 30 May 2012 (UTC)
   ┌────────────────────────────────────────────────────────────────┐
   │               ───── Some factorial lengths ─────               │
   │                                                                │
   │                   10 !  =           7  digits                  │
   │                   20 !  =          19  digits                  │
   │                   52 !  =          68  digits                  │
   │                  104 !  =         167  digits                  │
   │                  208 !  =         394  digits                  │
   │                  416 !  =         911  digits   (8 deck shoe)  │
   │                                                                │
   │                   1k !  =       2,568  digits                  │
   │                  10k !  =      35,660  digits                  │
   │                 100k !  =     456,574  digits                  │
   │                                                                │
   │                   1m !  =   5,565,709  digits                  │
   │                  10m !  =  65,657,060  digits                  │
   │                 100m !  = 756,570,556  digits                  │
   └────────────────────────────────────────────────────────────────┘  

In the table above, the factorial length for 416! should be 911 rather than 394. Used www.javascripter.net/math/calculators/100digitbigintcalculator.htm to verify.

01:27, 12 January 2015 (UTC)

Yes, it was inadvertently copied from the previous line. -- Gerard Schildberger (talk) 01:36, 12 January 2015 (UTC)

The moving of 80386 to x86 Assembly[edit]

I think it is better to use generic x86, and at most to specify a "works with", if needed, rather than let proliferate 80286, 80386, 80486, ... —ShinTakezou 14:56, 27 April 2010 (UTC)

I agree to a point; there's a definite progression and tendency toward backwards-compatibility. However, there are incompatible revisions. It's possible that different modes (real, protected, long and legacy) warrant some degree of recognition as their own languages--these modes represent forward and reverse compatibility constraints. --Michael Mol 16:03, 27 April 2010 (UTC)

D output[edit]

Is the   D   output supposed to show (eight times) the value of   (15!)   ? -- Gerard Schildberger (talk) 19:54, 26 May 2013 (UTC)

(This has been addressed and fixed.) -- Gerard Schildberger (talk) 21:44, 26 May 2013 (UTC)