How on Factorial

Dave Angel davea at
Thu Oct 28 16:13:15 CEST 2010

On 10/28/2010 10:01 AM, Xavier Ho wrote:
> On 28 October 2010 23:52, Dave Angel<davea at>  wrote:
>> The ~- trick only works on two's complement numbers.  I've worked on
>> machines in the past that used one's complement, and this wouldn't work
>> there.
>> DaveA
> I imagine this wouldn't work on floating point numbers either.
> Cheers,
> Xav
 From the help:

"The unary ~ (invert) operator yields the bitwise inversion of its plain 
or long integer argument. The bitwise inversion of x is defined as 
-(x+1). It only applies to integral numbers"

Inverting the bits of a floating point number wouldn't make much sense, 
so fortunately it gives an error.


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