Re: Re^2: Cleaning Data Between Specified Columns

Sorry Aristotle. Fletch's (partial) solution, neat as the technique is, falls foul of the fact that deleting the apostrophies in a one range, causes all the subsequent columns to shift.

Examine what is said, not who speaks.

The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.

Comment on Re: Re^2: Cleaning Data Between Specified Columns

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Re^4: Cleaning Data Between Specified Columns by Aristotle (Chancellor) on Jan 28, 2003 at 09:35 UTC
I should have tested. Anyway, in this case, it's a simple matter of changing the order of operations: `{ local _ = \substr $source, $start, $len; y/a-zA-Z0-9\n\\|-/ /c; y/'//d; }` [download] However, that obviously only works if there's only one operation affecting length. For a more general case, I'd do something like this (untested): #!/usr/bin/perl -w use strict; my @range = map /^(\d+)-(\d+)$/, sort { $a <=> $b } splice @ARGV, 1; unshift @range, 0; $range[$_] = 1 + $range[$_+1] - $range[$_] for 0 .. $#range-1; $range[-1] = ''; die "Negative length field specified" if grep $_ < 0, @range[0 .. $#range-1]; my $fmt = join " ", map "A$_", @range; # pick odd numbered elements my @selected = map 1 + $_ * 2, 0..$range_/2; while(<>) { my @field = unpack $fmt, $_; for (@field[@selected]) { tr/a-zA-Z0-9\n\\|\-'/ /c; tr/'//d; } print join '', @field; } [download] The point is to structure your data whenever possible. An array element end is never ambiguous, a `\x7F` can happen to be, and in my case, whatever my mark character, I've always been bitten by it. Makeshifts last the longest.	[reply] [d/l] [select]

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Re^4: Cleaning Data Between Specified Columns
by Aristotle (Chancellor) on Jan 28, 2003 at 09:35 UTC

{
    local *_ = \substr $source, $start, $len;
     y/a-zA-Z0-9\n\|-/ /c;
     y/'//d;
}
[download]

#!/usr/bin/perl -w
use strict;

my @range =
    map /^(\d+)-(\d+)$/,
    sort { $a <=> $b }
    splice @ARGV, 1;

unshift @range, 0;
$range[$_] = 1 + $range[$_+1] - $range[$_] for 0 .. $#range-1;
$range[-1] = '*';

die "Negative length field specified"
    if grep $_ < 0, @range[0 .. $#range-1];

my $fmt = join " ", map "A$_", @range;

# pick odd numbered elements
my @selected = map 1 + $_ * 2, 0..$range_/2;

while(<>) {
    my @field = unpack $fmt, $_;
    for (@field[@selected]) {
        tr/a-zA-Z0-9\n\|\-'/ /c;
        tr/'//d;
    }
    print join '', @field;
}
[download]

\x7F

can

Makeshifts last the longest.

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