Re^17: [OT] The interesting problem of comparing (long) bit-strings.

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Re^18: [OT] The interesting problem of comparing (long) bit-strings. by BrowserUk (Patriarch) on Mar 31, 2015 at 14:10 UTC
My code is pre-aligning the needle to a byte boundary, That would, for my purposes, mean that the entire needle would need to be copied, and the time taken counted. The reason is hinted at in the 6 argument function signature() I posted in the OP: `U64 bsSearch( U64 hay, U8 oHay, U64 lHay, U64 ndl, U8 oNdl, U64 lNdl + );` [download] Both the haystack and needle will be subsections of -- potentially much larger -- bitstrings; and shifting them in-place is not on, because they are effectively just windows into the parent bitstrings -- think substr refs. (Though I guess you might* be able to rotate them in place -- rotate so that no bits are lost -- then rotate them back afterwards; but again, the time taken would have to be counted.). That's why I'm now recoding in OO-style; so that the function signature can become: `bvSearch( BV hay, BV ndl );` and I can hide the nasty offsets, cross-boundary manipulations and (in particular) end-of-bitstring sub-64-bit bits behind the curtains. 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". I'm with torvalds on this In the absence of evidence, opinion is indistinguishable from prejudice. Agile (and TDD) debunked	[reply] [d/l] [select]

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Re^18: [OT] The interesting problem of comparing (long) bit-strings.
by BrowserUk (Patriarch) on Mar 31, 2015 at 14:10 UTC

My code is pre-aligning the needle to a byte boundary,

That would, for my purposes, mean that the entire needle would need to be copied, and the time taken counted.

The reason is hinted at in the 6 argument function signature(*) I posted in the OP:

U64 bsSearch( U64 *hay, U8 oHay, U64 lHay, U64 *ndl, U8 oNdl, U64 lNdl
+ );
[download]

Both the haystack and needle will be subsections of -- potentially much larger -- bitstrings; and shifting them in-place is not on, because they are effectively just windows into the parent bitstrings -- think substr refs. (Though I guess you might be able to rotate them in place -- rotate so that no bits are lost -- then rotate them back afterwards; but again, the time taken would have to be counted.).

That's why I'm now recoding in OO-style; so that the function signature can become: bvSearch( BV *hay, BV *ndl ); and I can hide the nasty offsets, cross-boundary manipulations and (in particular) end-of-bitstring sub-64-bit bits behind the curtains.

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". I'm with torvalds on this

In the absence of evidence, opinion is indistinguishable from prejudice. Agile (and TDD) debunked

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