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pranav0091

Arrays: Cant see where i'm going wrong

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I was toying around with AutoIt using it for simple automation until I got an assignment, which was basically to implement some data compression scheme and to comment on the compression ratio etc.

I have never done any project like this-which gives a finished product-on any programming language, though I'm decently conversed with C++ and a little bit with AutoIt.

So this time around I thought of using AutoIt for implementing the Lempel-Ziv algorithm. I got the code ready and it compiled okay, but the output wasn't what I expected. Then as a part of trouble shooting i got the generated code table and found that except for the first one, there's only one type of code - equivalent to the ASCII of "O".

Can anybody tell me where I'm going wrong ?

I looked around a lot, but cant figure out why I'm not able to generate different codes. So i'm attaching the code. Any help is appreciated.

Lempel_Ziv.au3

Note: The code for the algorithm itself is not "complete" in the sense that a few exceptions have not been covered yet.

Thanks in advance.

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I haven't tested the code, but looking through it, you have made an incorrect assumption in regards to FileRead. FileRead($ipfile, 1) reads in one CHARACTER, not one bit.


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I haven't tested the code, but looking through it, you have made an incorrect assumption in regards to FileRead. FileRead($ipfile, 1) reads in one CHARACTER, not one bit.

Thanks for pointing out the mistake. :)

Is there some way I can get the script to read the file bit by bit instead of reading one byte at a time?

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Is there some way I can get the script to read the file bit by bit instead of reading one byte at a time?

No. A Byte is the minimum data size for FileRead().

- You will need to use additional code to get at the bits of a Byte. (Give forum search a try, as there are some topics on that subject.)


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