Re^2: Unpack an 8 bit unsigned char matrix

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Re^3: Unpack an 8 bit unsigned char matrix (fixed) by BrowserUk (Patriarch) on Jul 15, 2013 at 22:06 UTC
A quick (not binary, but same difference) demo: `#! perl -slw use strict; use Data::Dump qw[ pp ]; sysread( DATA, my $buffer, 80 ) or die $!; my @matrixX10 = map[ unpack 'C', $_ ], unpack '(a10)', $buffer; pp\@matrixX10; my @matrixX5 = map[ unpack 'C', $_ ], unpack '(a5)', $buffer; pp\@matrixX5; __DATA__ 1234567890123456789012345678901234567890123456789012345678901234567890 +1234567890` [download] Produces: C:\test\primes>..\junk94 [ [49, 50, 51, 52, 53, 54, 55, 56, 57, 48], [49, 50, 51, 52, 53, 54, 55, 56, 57, 48], [49, 50, 51, 52, 53, 54, 55, 56, 57, 48], [49, 50, 51, 52, 53, 54, 55, 56, 57, 48], [49, 50, 51, 52, 53, 54, 55, 56, 57, 48], [49, 50, 51, 52, 53, 54, 55, 56, 57, 48], [49, 50, 51, 52, 53, 54, 55, 56, 57, 48], [49, 50, 51, 52, 53, 54, 55, 56, 57, 48], ] [ [49, 50, 51, 52, 53], [54, 55, 56, 57, 48], [49, 50, 51, 52, 53], [54, 55, 56, 57, 48], [49, 50, 51, 52, 53], [54, 55, 56, 57, 48], [49, 50, 51, 52, 53], [54, 55, 56, 57, 48], [49, 50, 51, 52, 53], [54, 55, 56, 57, 48], [49, 50, 51, 52, 53], [54, 55, 56, 57, 48], [49, 50, 51, 52, 53], [54, 55, 56, 57, 48], [49, 50, 51, 52, 53], [54, 55, 56, 57, 48], ] [download] Broken code replaced above: `#! perl -slw use strict; use Data::Dump qw[ pp ]; sysread( DATA, my $buffer, 80 ) or die $!; my @matrixX10 = map[ split 'C', $_ ], unpack '(a10)', $buffer; pp\@matrixX10; my @matrixX5 = map[ split 'C', $_ ], unpack '(a5)', $buffer; pp\@matrixX5; __DATA__ 1234567890123456789012345678901234567890123456789012345678901234567890 +1234567890` [download] Produces: C:\test>junk94 [ [1, 2, 3, 4, 5, 6, 7, 8, 9, 0], [1, 2, 3, 4, 5, 6, 7, 8, 9, 0], [1, 2, 3, 4, 5, 6, 7, 8, 9, 0], [1, 2, 3, 4, 5, 6, 7, 8, 9, 0], [1, 2, 3, 4, 5, 6, 7, 8, 9, 0], [1, 2, 3, 4, 5, 6, 7, 8, 9, 0], [1, 2, 3, 4, 5, 6, 7, 8, 9, 0], [1, 2, 3, 4, 5, 6, 7, 8, 9, 0], ] [ [1, 2, 3, 4, 5], [6, 7, 8, 9, 0], [1, 2, 3, 4, 5], [6, 7, 8, 9, 0], [1, 2, 3, 4, 5], [6, 7, 8, 9, 0], [1, 2, 3, 4, 5], [6, 7, 8, 9, 0], [1, 2, 3, 4, 5], [6, 7, 8, 9, 0], [1, 2, 3, 4, 5], [6, 7, 8, 9, 0], [1, 2, 3, 4, 5], [6, 7, 8, 9, 0], [1, 2, 3, 4, 5], [6, 7, 8, 9, 0], ] [download] 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". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l] [select]
Re^3: Unpack an 8 bit unsigned char matrix by BrowserUk (Patriarch) on Jul 15, 2013 at 21:56 UTC
I apologise. I omitted an essential part of the first unpack template (the repeat ). Please try substituting this: `my @matrix = map[ unpack 'C', $_ ], unpack '(a' . NCOLS . ')', $buff +er;` [download] The template has become: `'(a3954)'` which tells unpack to split the buffer into as many 3954-byte chunks as are available. 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". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l] [select]


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