Peter wrote regarding 'Re: [EE] Big numbers' on Thu, Apr 20 at 14:05:
> 
> On Thu, 20 Apr 2006, YAP wrote:
> 
> > What is 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF (128 bits) in decimal?  How go a
> > head an calculate big numbers like this.
> 
> plp@plp:~$ bc -l
> bc 1.06

Somewhat interestingly, this led me to find that perl apparently can't
cope with hex numbers greater than 32 bits on my 32-bit processor,
even with the bignum module loaded...

[danny@random-machine]$ perl -Mbignum -le'print hex("F"x8)'
4294967295
[danny@random-machine]$ perl -Mbignum -le'print hex("F"x9)'
Integer overflow in hexadecimal number at -e line 1.
68719476735
[danny@random-machine]$ perl -Mbignum -le'print hex("F"x32)'
Integer overflow in hexadecimal number at -e line 1.
3.40282366920938e+38

And printf sucks

[danny@random-machine]$ perl -e'printf "%d\n", 0xFFFFFFFFFFFFFFFF'
Integer overflow in hexadecimal number at -e line 1.
-1

But it works fine with the same non-hex numbers...

[danny@random-machine]$ perl -le'print 2**128 - 1'
3.40282366920938e+38
[danny@random-machine]$ perl -Mbignum -le'print 2**128 - 1'
340282366920938463463374607431768211455

And, BTW, you can pipe math into bc - which is something I used
somewhat regularly...

[danny@random-machine]$ echo "(2^128)-1" | bc
340282366920938463463374607431768211455

Anyway, it was interesting to me, so I figured at least one other
person might agree. :)

--Danny, obviously just killing time
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