in reply to Re: Hash of Arrays and File Operations
in thread Hash of Arrays and File Operations

I am trying to use map but it doesn't seem to be working. I tried doing it as : 

@cols[1 .. $#cols] = map(tr /[1,2]/[0,1]/, @cols)

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Also, do u think doing (i)split and getting the values as $id and @cols; then doing (ii)join to get the cols as scalar values so that we can do translate and then do (iii) split again to get the array value so that I can store it in the hash of arrays a good idea ?? for eg: 

my %data;
while (<DATA>) {
    next if /^id/;
    my ($id, @cols) = split; ## first split
    my $cols = join('',@cols); ## Join 
    @cols = split('',$cols); ## and then split
    push @{ $data{$id} }, \@cols;
}

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I am having second thoughts about this method as it may lead to slower process or it might not be a good programming practice. Please Advise.

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Re^3: Hash of Arrays and File Operations
by toolic (Bishop) on Jan 28, 2010 at 20:15 UTC 
    @cols[1 .. $#cols] = map(tr /[1,2]/[0,1]/, @cols)

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    I'm no tr expert, but isn't tr /[1,2]/[0,1]/ more simply written as tr/12/01/?

    The following will replace all 1's with 0's, and all 2's with 1's, in all elements of the @cols array. It modifies the array in-place. 

    map { tr/12/01/ } @cols;

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    Update: I concur with AnonyMonk's hint that it is better written as: 

    tr/12/01/ for @cols;

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[d/l]
[select]
      tr/12/91/ for @cols[1.. $#cols];
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[d/l]

        I have tried the above syntax and it doesn't seem to be working.

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