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From: supergems on 9 Apr 2010 11:25
@Teuvo Yrjömäki thanks for your program. I rewrote it in ASCII format:

\<< 0 \-> ACC
\<< DUP2 B\->R .001 + LOG 2 LOG /
IP SWAP B\->R .001 + LOG 2 LOG /
IP MAX 0 SWAP 1 +
FOR X DUP2 # 1b AND SWAP
# 1b AND
IF \=/
THEN ACC 1 + 'ACC' STO
END SR SWAP SR
NEXT DROP2 ACC
\>>
\>> 'HAMDIST' STO

Ex. # 1101101b # 1110011b HAMDIST --> 4

@Dave Hayden and Michael J. Schülke thanks for your suggestion to use
the BITS program of Jurjen NE Bos:

\<< # 7777777777777777h OVER SR
OVER AND DUP2 SR AND ROT OVER SR
AND + + - DUP SR SR SR SR +
# F0F0F0F0F0F0F0Fh AND # FFh
DUP2 / * - \>> 'BITS' STO

Ex. # 1101101b # 1110011b XOR --> # 11110b (here already we see the
number of bits)
and then with BITS we get # 100b which is # 4d

supergems
From: Han on 9 Apr 2010 16:41
On Apr 9, 8:29 am, "Michael J. Schülke" <n...(a)mjschuelke.de> wrote:
> Dave Hayden schrieb:
>
> > Given two binary numbers A and B, then Hamming distance is the number
> > of "1" bits in (A AND B).
>
> A XOR B, surely?
>
> Regards,
> Michael

Yes, I believe XOR is the correct operation, not AND. Hamming distance
is the number of positions in which there differences. The wiki page
explains this clearly.
From: Virgil on 9 Apr 2010 17:05
In article
<1f9d829d-487e-4078-b090-57bb451a216a(a)c36g2000yqm.googlegroups.com>,
supergems <simone.cerica(a)gmail.com> wrote:

> Hi, how can we calculate the Hamming distance (
> http://en.wikipedia.org/wiki/Hamming_distance
> ) between two binary numbers? For example, the Hamming distance
> between 1011101 and 1001001 is 2.
>
> supergems

Short program to count the one bits in a binary number:

With binary number on the stack execute


\<< # 0b SWAP
WHILE DUP # Ob >
REPEAT DUP # 1b AND ROT + SWAP SR
END
DROP B\->R
\<<


Thus to find the Hamming distance between two binary numbers you could
either XOR the numbers first and use the above program or use the
slightly longer program:

\<< XOR # 0b SWAP @ or #0 in whatever base you are using
WHILE DUP # Ob >
REPEAT DUP # 1b AND ROT + SWAP SR
END
DROP B\->R
\<<

Note that the "b" in the above presumes base two, but since the only
binary numbers entered are # 0 and # 1, which are the same in all bases
except for the base indicator, the base actually activated does not
matter.
From: supergems on 10 Apr 2010 02:40
On 9 Apr, 23:05, Virgil <Vir...(a)home.esc> wrote:
> In article
> <1f9d829d-487e-4078-b090-57bb451a2...(a)c36g2000yqm.googlegroups.com>,
>
>  supergems <simone.cer...(a)gmail.com> wrote:
> > Hi, how can we calculate the Hamming distance (
> >http://en.wikipedia.org/wiki/Hamming_distance
> > ) between two binary numbers? For example, the Hamming distance
> > between 1011101 and 1001001 is 2.
>
> > supergems
>
> Short program to count the one bits in a binary number:
>
> With binary number on the stack execute
>
> \<< # 0b  SWAP        
>     WHILE DUP # Ob >
>     REPEAT DUP # 1b AND ROT + SWAP SR
>     END
>     DROP B\->R
> \<<
>
> Thus to find the Hamming distance between two binary numbers you could
> either XOR the numbers first and use the above program or use the
> slightly longer program:
>
> \<< XOR # 0b  SWAP          @ or #0 in whatever base you are using
>     WHILE DUP # Ob >
>     REPEAT DUP # 1b AND ROT + SWAP SR
>     END
>     DROP B\->R
> \<<
>
> Note that the "b" in the above presumes base two, but since the only
> binary numbers entered are # 0 and # 1, which are the same in all bases
> except for the base indicator, the base actually activated does not
> matter.

Thank you very much Virgil! :-)
From: Virgil on 10 Apr 2010 16:57
In article
<e306448c-165a-419b-9aff-c4133a0747eb(a)b33g2000yqc.googlegroups.com>,
supergems <simone.cerica(a)gmail.com> wrote:

> On 9 Apr, 23:05, Virgil <Vir...(a)home.esc> wrote:
> > In article
> > <1f9d829d-487e-4078-b090-57bb451a2...(a)c36g2000yqm.googlegroups.com>,
> >
> > �supergems <simone.cer...(a)gmail.com> wrote:
> > > Hi, how can we calculate the Hamming distance (
> > >http://en.wikipedia.org/wiki/Hamming_distance
> > > ) between two binary numbers? For example, the Hamming distance
> > > between 1011101 and 1001001 is 2.
> >
> > > supergems
> >
> > Short program to count the one bits in a binary number:
> >
> > With binary number on the stack execute
> >
> > \<< # 0b �SWAP � � � �
> > � � WHILE DUP # Ob >
> > � � REPEAT DUP # 1b AND ROT + SWAP SR
> > � � END
> > � � DROP B\->R
> > \<<
> >
> > Thus to find the Hamming distance between two binary numbers you could
> > either XOR the numbers first and use the above program or use the
> > slightly longer program:
> >
> > \<< XOR # 0b �SWAP � � � � �@ or #0 in whatever base you are using
> > � � WHILE DUP # Ob >
> > � � REPEAT DUP # 1b AND ROT + SWAP SR
> > � � END
> > � � DROP B\->R
> > \<<
> >
> > Note that the "b" in the above presumes base two, but since the only
> > binary numbers entered are # 0 and # 1, which are the same in all bases
> > except for the base indicator, the base actually activated does not
> > matter.
>
> Thank you very much Virgil! :-)

Glad to be of use.
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