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Postings from April 2012
On Monday 23,April,2012 01:27 AM, Jim Gibson wrote:
>
> On Apr 22, 2012, at 9:52 AM, lina wrote:
>
> Here is what I Have came up so far,
>>
>> #!/usr/bin/env perl
>>
>> use strict;
>> use warnings;
>> use autodie qw(open close);
>> use 5.012;
>>
>> my $dict = system("tail -n 1 text_1.xvg");
>
> Read the documentation on the system function. It does not return the output of the child process to your program. For that, you need the qx() operator, or backticks:
>
> my $dict = qx("tail -n 1 text_1.xvg");
>
>> print $dict;
>> print "\n\n";
>> open my $fh, "<","text_2.xvg";
>> while(<$fh>){
>> print $_;
>> }
>
> Of course, it is possible to read the last line of a file without resorting to creating a child process. See, for example, the module File::ReadBackwards.
>
>
Thanks.
Here I came up a working script (unavoidably clumsy).
I don't know how to refine it, or make it terse.
Thanks ahead for your time,
#!/usr/bin/env perl
use strict;
use warnings;
use autodie qw(open close);
use 5.012;
open my $fh1, "<","text_1.xvg";
my $lastline;
my %dict;
my @lastline;
my $n;
while(<$fh1>){
$lastline = $_ if eof;
}
@lastline = split /[\t ]/,$lastline;
$n = shift @lastline;
foreach my $i (0..3){
$dict{$i}=$lastline[$i]
}
open my $fh, "<","text_2.xvg";
my @old;
while(<$fh>){
$n+=2;
my @old = split /\s*/,$_;
shift @old;
foreach my $item (@old){
s/$item/$dict{$item}/g;
}
print $n, "\t", join " ", @old;
print "\n";
}
$ more text_1.xvg
0 0 1 2 3
2 1 0 2 3
4 1 2 0 3
$ more text_2.xvg
0 0 1 2 3
2 1 0 3 2
4 1 3 0 2
output
$ ./renumber_v1.pl
6 0 1 2 3
8 1 0 3 2
10 1 3 0 2
Best regards,