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Want to split a file into columns

P: n/a
Hi All;

I am fairly new to Perl. I have a file with close to 3000 lines
that I would like to split out in a certain way. I would like to put
the record type starting in column 1 for 2 spaces, the employer code
in column 23 for 29 spaces and employer description in column 53 for
30 spaces. I have tried modifying an existing file with no real
success. I haven't found anything that specifically answers my
question. Any guidance would be appreciated.

My input file would look like this

09 A/B A & B Construction Co.

I'm working on a script so that I don't have to move all of these
manually. The code I am working on is the following. I didn't want to
delete anything, so that is why a good bit of it is commented out.
Thanks in Advance


my ($mday,$mon,$year) = (localtime(time))[3,4,5];
$year -= 100 ;
$mon++;
my $date = sprintf("%02d%02d%02d%02d","20",$year,$mon,$mday);
my @records = ( );
$infile .= '.' . $date;
open(INPUT, $infile) or die "Unable to open $infile: $!\n";
#@lines = <INPUT>; # reads in all lines when called like this
my $inrecord = 0;
my $i = -1; # $i++ the first time will make this 0

while(<INPUT>) {
#($a,$b,$c)=split(" ",$string);
$str=split(" ",split,3);

#my $a = substr(1, 2);
#my $b = substr(23, 29);
#my $c = substr(53, 29);

#print $str[0];
#print " ";
#print $str[1];
#print " ";
#print $str[2];
#print "\n";
}
close(INPUT);
my $record;
open(OFH, '>' . $outfile) or die $!;
for $record (@records) {
# split it up per-line
#for $line (split(/\r?\n/, $record)) {
#my $a = substr($line, 1, 2);
#my $b = substr($line, 23, 29);
#my $c = substr($line, 53, 29);

#print @records;
#print "TESTING!!! \n";
#print $a;
#print " ";
#print $string;
#print " ";
#print $c;
#print $line;
#print "\n";
#print $record;
#print "\n";

#print OFH $record;

#open(OFH, '>' . $outfile) or die $!;

# my $a = substr($a, 1, 2);
# my $b = substr($b, 23, 29);
# my $c = substr($c, 53, 29);

# print the whole $record to the outfile
# print OFH $a,$b,$c;
#}
}
# }
#}
close(OFH);
Jul 19 '05 #1
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2 Replies


P: n/a
SL_McManus wrote:
Hi All;

I am fairly new to Perl. I have a file with close to 3000 lines
that I would like to split out in a certain way. I would like to put
the record type starting in column 1 for 2 spaces, the employer code
in column 23 for 29 spaces and employer description in column 53 for
30 spaces. I have tried modifying an existing file with no real
success. I haven't found anything that specifically answers my
question. Any guidance would be appreciated.

My input file would look like this

09 A/B A & B Construction Co.

Well, there's more than one way to do it (hey, this is Perl, right? :-))
I usually wimp out with a regular expression something like this

while (<>) {
my ($first, $second, $third) = /^(.{2})(.{29})(.{30})/;
print "$first\n$second\n$third\n\n";
}

HTH

David

--

We come here upon what, in a large proportion of cases, forms the
source of the grossest errors of mankind. Men on a lower level of
understanding, when brought into contact with phenomena of a higher
order, instead of making efforts to understand them, to raise
themselves up to the point of view from which they must look at the
subject, judge it from their lower standpoint, and the less they
understand what they are talking about, the more confidently and
unhesitatingly they pass judgment on it.

-- Leo Tolstoy, "The Kingdom of God is Within You"
Jul 19 '05 #2

P: n/a
In article <b2**************************@posting.google.com >,
SL_McManus <sl*********@netzero.net> wrote:
Hi All;

I am fairly new to Perl. I have a file with close to 3000 lines
that I would like to split out in a certain way. I would like to put
the record type starting in column 1 for 2 spaces, the employer code
in column 23 for 29 spaces and employer description in column 53 for
30 spaces. I have tried modifying an existing file with no real
success. I haven't found anything that specifically answers my
question. Any guidance would be appreciated.

My input file would look like this

09 A/B A & B Construction Co.

I'm working on a script so that I don't have to move all of these
manually. The code I am working on is the following. I didn't want to
delete anything, so that is why a good bit of it is commented out.
Thanks in Advance
In fact, most of it is commented out. You really should only post a
working (syntax-error-free) program so people can answer specific
questions. It is hard to tell if you want guidance on the uncommented
out or the commented out code. I will assume the former.


Add the following to get help from perl:

use strict;
use warnings;
use diagnostics;


my ($mday,$mon,$year) = (localtime(time))[3,4,5];
$year -= 100 ;
$mon++;
my $date = sprintf("%02d%02d%02d%02d","20",$year,$mon,$mday);
my @records = ( );
$infile .= '.' . $date;
You need a 'my' in front of $infile now that you have 'use strict;' in
your program. You haven't initialized $infile previously, so you are
adding ".$date" to an empty string. Is the file you want to read really
named something like '.20031001'?
open(INPUT, $infile) or die "Unable to open $infile: $!\n";
#@lines = <INPUT>; # reads in all lines when called like this
my $inrecord = 0;
my $i = -1; # $i++ the first time will make this 0
You don't seem to use $inrecord or $i below, so these could be removed.

while(<INPUT>) {
#($a,$b,$c)=split(" ",$string);
$str=split(" ",split,3);
This won't work. You are using the function split twice here. The line
you just read is in $_, so you should at least be using split("
",$_,3). Of course, 'split(" ",...' won't work if you have spaces in
your field, which your example does. Also, you are assigning the return
from the split function to a scalar, so you will get only the number of
fields split and not the fields themselves. The split data actually
ends up in the @_ array, but you probably didn't know that (I didn't
until I looked it up).

Look at the unpack function instead, or use the substr calls you have
commented out below. Something like this might work, if your fields are
fixed width in the columns implied by your substr calls, although the
example data line you gave above doesn't match them (untested):

($type,$code,$name) = unpack("A2x19A29A29",$_);

Of course, these seem to be your desired output format, so your likely
input format is something else. According to the sample data, this
should be

($type,$code,$name) = unpack("A2x2A3x4A*",$_);

#my $a = substr(1, 2);
#my $b = substr(23, 29);
#my $c = substr(53, 29);

#print $str[0];
#print " ";
#print $str[1];
#print " ";
#print $str[2];
#print "\n";
}
close(INPUT);
my $record;
open(OFH, '>' . $outfile) or die $!;
You don't have anything in $outfile, so this will not succeed.
for $record (@records) {
You don't have anything in @records, so this will do nothing, but then
the rest of your loop is commented out so will do nothing in any case.
# split it up per-line
#for $line (split(/\r?\n/, $record)) {
#my $a = substr($line, 1, 2);
#my $b = substr($line, 23, 29);
#my $c = substr($line, 53, 29);

#print @records;
#print "TESTING!!! \n";
#print $a;
#print " ";
#print $string;
#print " ";
#print $c;
#print $line;
#print "\n";
#print $record;
#print "\n";

#print OFH $record;

#open(OFH, '>' . $outfile) or die $!;

# my $a = substr($a, 1, 2);
# my $b = substr($b, 23, 29);
# my $c = substr($c, 53, 29);

# print the whole $record to the outfile
# print OFH $a,$b,$c;
#}
}
# }
#}
close(OFH);


I suggest you look at the unpack and printf functions:

perldoc -f unpack
perldoc -f printf

I suggest you open the output file at the same time as the input file,
read each record, extract the fields, and write them to the new file.

Something like this (untested):

#!/opt/perl/bin/perl

use strict;
use warnings;
use diagnostics;

my $infile = 'old.dat';
my $outfile = 'new.dat';
open(INPUT, $infile) or die "Unable to open $infile: $!\n";
open(OUTPUT, $outfile) or die "Unable to open $outfile: $!\n";
while(defined(my $line=<INPUT>)) {
my ($type,$code,$name) = unpack("A2x19A29A29",$_);
printf OUTPUT "%2s%19s%29s%30s\n", $type, '', $code, '', $name;
}
close(INPUT);
close(OUTPUT);
Jul 19 '05 #3

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