There were many typos in the book – back in they days when we printed long listings like this, it was tough on the proofreaders – they didn’t understand C. Not only that, but the people who typeset the book had to take my code for printouts and type it in by hand – and they didn’t know C either.

The disk that accompanied the book had correct code, but if you are looking at the book right now it is very unlikely that you have a copy of the diskette.

The line in question should be:

min_2 = min_1;

Somehow that = sign was converted to a plus sign.

Thanks for reading!
- Mark

Thank you for answer

THANKS

I would really love to update the book, but I don’t have the time in my schedule in the near future.

- Mark

I’ve given the best explanation I know how in the book. It’s possible you might get a better explanation here, but it’s mostly the same text as the book:

http://dogma.net/markn/articles/arith/part1.htm

You could try the wikipedia article also:

http://en.wikipedia.org/wiki/Arithmetic_coding

I recommend actually running the code in a debugger and stepping through it for better results.

I have read your book “The Data Compression” and just have one question about ‘The Arithmatic code method’, I can’t find an example of decoding the example message “BILL GATE” by shifting the MSB from low and High values. I will appreciate that if you can give me the decoding example as I understood the encoding but can’t understood the decoding from the C code.

Best Wishes

Yaser Hosaney
Egypt

Thanks for the corrections – the first edition was done in the dark ages of publishing – believe it or not I had to send in hardcopy, so it had more than it’s share of problems, particularly in the code.

- Mark

Love the book. It’s been on my bookshelf since ’92.

I was referring to it this morning, and thought I’d pass along some errata, in case you plan to come out with a revised edition sometime soon.

These are pertaining to the first edition.

Page 125, in your table, all 18 of your “greater than” signs should be “less than signs”. Example,
SPACE 1/10 0.00 >= r > 0.10
(no value of r can be both less than 0 and greater than 0.1)

Page 234, second last paragraph ends with:
So this token is encoded as: 14, 4, ‘ .’ – which should be
So this token is encoded as: 14, 4, ‘ ‘.
(I’m sure some English-expert editor (or program) incorrectly put the period inside the quote for you. If you want to satisfy the editor, perhaps put it inside of double quotes, like you did on page 235:
So this token is encoded as: “14, 4, ‘ ‘.”

I found a few more minor things… not sure if you want them. Very helpful book, though! Thanks!