Re^4: comparison of packed signed integers

Yes, but the same holds true using 'l>'.

knoppix@Microknoppix:~$ perl -E '
> $pos = pack q{l>}, 10000;
> say unpack q{B*}, $pos;
> $neg = pack q{l>}, -10000;
> say unpack q{B*}, $neg;
> say $pos gt $neg ? q{Good} : q{Bad};'
00000000000000000010011100010000
11111111111111111101100011110000
Bad
knoppix@Microknoppix:~$
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I think that packing with 'N' or 'l>' will always produce the same results, it is unpacking where it makes a difference.

knoppix@Microknoppix:~$ perl -E '
> for ( -2147483648, -1, 0, 1, 2147483647, 4294967295 )
> {
>     say qq{$_:};
>     say unpack q{B*}, pack q{N}, $_;
>     say unpack q{B*}, pack q{l>}, $_;
>     say q{-} x 32;
> };
> '
-2147483648:
10000000000000000000000000000000
10000000000000000000000000000000
--------------------------------
-1:
11111111111111111111111111111111
11111111111111111111111111111111
--------------------------------
0:
00000000000000000000000000000000
00000000000000000000000000000000
--------------------------------
1:
00000000000000000000000000000001
00000000000000000000000000000001
--------------------------------
2147483647:
01111111111111111111111111111111
01111111111111111111111111111111
--------------------------------
4294967295:
11111111111111111111111111111111
11111111111111111111111111111111
--------------------------------
knoppix@Microknoppix:~$
[download]

However, I'm happy to be corrected if I'm wrong.

Cheers,

JohnGG

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Re^5: comparison of packed signed integers by BrowserUk (Patriarch) on Oct 30, 2011 at 12:33 UTC
However, I'm happy to be corrected if I'm wrong. You're not wrong! Thanks for the reality check. It will only work with unsigned big-endian. I'll update my post above. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]

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Re^5: comparison of packed signed integers
by BrowserUk (Patriarch) on Oct 30, 2011 at 12:33 UTC

However, I'm happy to be corrected if I'm wrong.

You're not wrong! Thanks for the reality check.

It will only work with unsigned big-endian. I'll update my post above.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

[reply]