in reply to Re: How do I convert a very long bit string into a number?
in thread How do I convert a very long bit string into a number?
This can be generalised for other orderings of the bytes, and of the bits in each byte, of the bitstring. Four types of bitstring can be identified:
big-endian: ms-bit of first byte is the ms-bit of the multi-byte number. This is handled as shown, ie:
my $h = unpack( 'H*', $bitstring ) ;
little-endian: ls-bit of first byte is the ls-bit of the multi-byte number. This is handled:
Note that this is the same order as vec($v, $b, 1)my $h = unpack( 'H*', scalar reverse $bitstring ) ;
big-endian reversed bytes: ls-bit of first byte is the ms-bit of the multi-byte number. This is handled:
my $h = unpack( 'H*', pack('b*', unpack('B*', $bitstring)) ) ;
little-endian reversed bytes: ms-bit of first byte is the ls-bit of the multi-byte number. This is handled:
my $h = unpack( 'H*', pack('b*', unpack('B*', scalar reverse $bitstr +ing)) ) ;
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