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print +split

by drock (Beadle)
on Mar 13, 2005 at 00:28 UTC ( [id://439031]=perlquestion: print w/replies, xml ) Need Help??

drock has asked for the wisdom of the Perl Monks concerning the following question:

WITH the $diff code it is NOT subtracting the two numbers which is what I need. I think the problem is $_ contains data from the original app command which is regular files 62,622 597.488G 641547379187 archdone files 62,535 597.008G 641032761295 and so I am saying subtract what is in field 1 , well field 1 is empty, but why???? finally, I took away the + from the print and I had some errors, why is the + infront of the split needed in Perl? thank you, derek
my $dev = qw/original1/; my $dev1 = qw/clinical1/; my $diff=0; open (FOO, "samcmd a $dev 2>\&1 |" ) || die "unable to open pipe... Broken? $!"; while (<FOO>) { if (/regular files|archdone files/) { local $, = "\n"; #s/^\w+(\s+)\w+(\s+)// && s/,//,; s/,//, print +(split)[2], $,; if (/^\d+/) { diff -=$1; ##--## 62622-62535 } } } print "Difference is: $diff\n"; close (FOO) or warn "unable to close file $!"; __DATA__ regular files 62,622 597.488G 641547379187 archdone files 62,535 597.008G 641032761295

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Re: print +split
by Roy Johnson (Monsignor) on Mar 13, 2005 at 00:51 UTC
    The + is there to keep print from thinking those parentheses contain its argument. You are missing the $ on diff in your if. The if doesn't match because the line does not start with digits.
    use strict;
    would have helped you some. Some judicious print statements would also be enlightening. The code is getting pretty bletcherous. Did you copy some of these constructs?

    I've updated it just enough that it runs and you can see what you've got. I don't know where you want to take it from here.

    use strict; use warnings; my $dev = qw/original1/; my $dev1 = qw/clinical1/; my $diff=0; # open (FOO, "samcmd a $dev 2>\&1 |" ) || die # "unable to open pipe... Broken? $!"; while (<DATA>) { if (/regular files|archdone files/) { local $, = "\n"; #s/^\w+(\s+)\w+(\s+)// && s/,//,; s/,//, print +(split)[2], $,; if (/^\d+/) { $diff -=$1; ##--## 62622-62535 } else { print "$_ does not start with digits.\n"; } } } print "Difference is: $diff\n"; #close (FOO) or warn "unable to close file $!"; __DATA__ regular files 62,622 597.488G 641547379187 archdone files 62,535 597.008G 641032761295

    Caution: Contents may have been coded under pressure.
      yes Roy, thanks but I intended to paste everything including use strict, but forgot. The missing $ was a mistake...sorry I have the same code and it is not subtracting the two values 62622 and 62535.
      use strict; use warnings; use diagnostics; use MIME::Lite; use Logfile::Rotate; $ENV{"PATH"} = qq(/opt/SUNWsamfs/sbin:/usr/bin:/usr/sbin:/usr/local/lo +g); ########## ## Fuji ## ########## my $dev = qw/original1/; my $dev1 = qw/clinical1/; my $diff=0; open (FOO, "samcmd a $dev 2>\&1 |" ) || die "unable to open pi +pe... Broken? $!"; while (<FOO>) { if (/regular files|archdone files/) { local $, = "\n"; #s/^\w+(\s+)\w+(\s+)// && s/,//,; s/,//, print +(split)[2], $,; if (/^\d+/) { $diff -=$2; ##--## 62622 - 62535 # I dont really need this if b/c # I know what $_ contains after the split # which is the two numbers. } } } __DATA__ regular files 62,622 597.488G 641547379187 archdone files 62,535 597.008G 641032761295
        Try:
        while (<DATA>) { if (/regular files|archdone files/) { local $, = "\n"; s/,//; print +(split)[2], $,; $diff[++$i] = (split)[2]; } } print $diff[1]-$diff[2],"\n"; __DATA__ regular files 62,622 597.488G 641547379187 archdone files 62,535 597.008G 641032761295

        Your code wasn't performing a subtraction. Also, as Roy mentioned the /^\d+/ wasn't matching.
Re: print +split
by chas (Priest) on Mar 13, 2005 at 00:48 UTC
    In print +(split)[2], $,;, the "+" prevents the following parentheses from being interpreted as part of a function call to print; it has no other effect.
    chas
    (Update: I meant to add some more comments but accidently created instead of previewing; another reply had already appeared.)
      ok thanks chas! : )

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