Thank you for this.

As a first pass (of what is perhaps the most opaque algorithm description I've yet encountered), this does far more work than I see being necessary for my particular problem; as such I think it would be necessary to adapt it quite heavily to only do that which I need.

My, currently fragile, implementation of the running checksum algorithm works (so far tested on a very limited set of cases):

[15:15:42.17] C:\test>rollingChksum -MAX=1e6 -BUF=1e3 -WRAP=9.123e5
6891
910000
Found repeat starting at value:912300

[15:15:48.65] C:\test>

[15:16:17.32] C:\test>rollingChksum -MAX=1e7 -BUF=1e3 -WRAP=9.123e6
6891
9120000
Found repeat starting at value:9123000

[15:17:22.49] C:\test>

[download]

Needs a lot of work, and a lot more testing, but it is currently processing around 6MB(16bit values, not bytes)/second; and I know that can be sped up by at least 10 times by optimising the Perl; and much further still, once I recode the algorithm into C.

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". The enemy of (IT) success is complexity.
In the absence of evidence, opinion is indistinguishable from prejudice. Suck that fhit

In reply to Re^2: Algorithm inspiration required. by BrowserUk
in thread Algorithm inspiration required. by BrowserUk

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