data inside file

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

Hi Monks, I have a file that contains some employee information .. sort schedulling file. I need to update the file and sechdul more people however , I wana make sure I am not sechdulling the same person based on thier number the data file looks like this :

data
----
Loc     num     name    age     car     $$
817     09      Sam     99      TU      300
444     11      Ram     88      CM      7
111     3       Kin     8       RT      88
[download]

so the key will be the num ,if the employee number exists then error. I was doing the following:


my $empNUM;

open(DATA, "data") or die ; 
open(UPDAT, ">updated") or die;
while(<DATA>)
{
my @line = split(/ /, $_);
foreach $line (@line)
{
if ($line[2] eq $empNum){exit 0;}
}
}end loop
print UPDAT $details;
close(DATA);
close(UPDAT);
[download]

since I am new to perl , I don't think this is the wise way of doing it , any advice on doing this? thanks

Comment on data inside file Select or Download Code

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Re: data inside file by AcidHawk (Vicar) on May 11, 2004 at 20:16 UTC
I am not sure what you are trying, but a few comments. You declare `my $empNUM;` but later refer to `$empNum` - Possible Type ?? since you are using `my` try to be consistant.. so you line `foreach $line (@line)` would look like `foreach my $line (@line)` instead of exiting I.e. `exit 0;` you might have employees to process after you found a match so instead do a `next` So you might end up with something like `my $empNUM; open(DATA, "data") or die ; open(UPDAT, ">updated") or die; while(<DATA>) { my @line = split(/\s+/, $_); #Assuming your file is split on multi +ple spaces..? if ($line[2] eq $empNUM){ next; } else { print UPDAT "$_"; } } close(DATA); close(UPDAT);` [download] Update: Removed the foreach as it is not necessary.. ----- Of all the things I've lost in my life, its my mind I miss the most.	[reply] [d/l] [select]
Re: data inside file by mifflin (Curate) on May 11, 2004 at 20:24 UTC
try `@line = split /\s+/, $_;` [download] as your split. \s is matches whitespace. The plus sign says one or more of the prior character. Note: you really dont need th $_ in the split statement. By default split uses $_ so your split line could look like... `@line = split /\s+/;` [download]	[reply] [d/l] [select]
Re: data inside file by saintbrie (Scribe) on May 11, 2004 at 23:44 UTC
You probably want to look at using a hash lookup, instead of an array. `my %lookup = (); # initialize the hash while (defined ($line = <DATA>)) { my @line = split /\s+/, $line; if (defined ($lookup{$line[1]})) { # array indexes start at 0 # if the hash key already has been defined (see below)... exit(0); # error out; } else { $lookup{$line[1]} = 1; # define the lookup value; } }` [download]	[reply] [d/l]
Re: data inside file by nothingmuch (Priest) on May 11, 2004 at 20:05 UTC
The criteria for split is not good, because the match will not split columns. Read perlretut and split to see how to write an appropriate regex. `end loop` is not valid perl, you ought to comment it f that's what you mean. Think what happens to the data after the line you updated. Unless this is home work, there are many modules on the CPAN to help deal with serialized tables of any sort, from CSVs to an SQL server's tables. Perhaps most notable is the AnyData namespace. -nuffin zz zZ Z Z #!perl	[reply] [d/l]