Re^5: pack/unpack 6-bit fields. (Different types of sanity)

in reply to Re^4: pack/unpack 6-bit fields. (insanity)
in thread pack/unpack 6 bit fields.

Comment on Re^5: pack/unpack 6-bit fields. (Different types of sanity)

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Re^6: pack/unpack 6-bit fields. (insanity) by tye (Sage) on Aug 18, 2004 at 21:55 UTC
My numbers look correct to me. `print unpack 'B', 'twelve bytes'; ## hand spaced 001011 101110 111010 100110 001101 100110 111010 100110 000001 000100 011010 011110 001011 101010 011011 001110` [download] You show code containing `'B'` but the bits that you show are from using `'b'`. That is why you can match the 'b' case against it. Trying to match the 'B' against that string gives one of the less-sane results I mentioned (where the bit orders are mismatched). To be extra clear, using 'B' would result in each group of 8 bits being reversed (it doesn't reverse the whole bit string), which results in different 6-bit chunks not just reversed 6-bit chunks (so neither of your cases cover it). - tye	[reply] [d/l]

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Re^6: pack/unpack 6-bit fields. (insanity)
by tye (Sage) on Aug 18, 2004 at 21:55 UTC

My numbers look correct to me.

print unpack 'B*', 'twelve bytes'; ## hand spaced 001011 101110 111010 100110 001101 100110 111010 100110 000001 000100 011010 011110 001011 101010 011011 001110
[download]

You show code containing 'B*' but the bits that you show are from using 'b*'. That is why you can match the 'b*' case against it.

Trying to match the 'B*' against that string gives one of the less-sane results I mentioned (where the bit orders are mismatched).

To be extra clear, using 'B*' would result in each group of 8 bits being reversed (it doesn't reverse the whole bit string), which results in different 6-bit chunks not just reversed 6-bit chunks (so neither of your cases cover it).

- tye

[reply]
[d/l]

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