Hi Rajeev,
some comments on your code:
On Fri, 2 Sep 2011 13:28:49 -0700 (PDT)
Rajeev Prasad <rp.ne...@yahoo.com> wrote:
>
> unfortunately it was not working as i intended.
>
> so i have new code with some help now:
> using $column variable, i can control which column (from 1 to 4) i want to be
> printed with column 5.
Add "strict" and "warnings".
> open(IN_FH,"<","infile") or die "Cannot open infile because: $!";
> open(OUT_FH,">","outfile") or die "Cannot open outfile because: $!";
Always use lexical filehandles:
[CODE]
open(my $in_fh,"<","infile") or die "Cannot open infile because: $!";
[/CODE]
But it's good that you've used three-args open followed by "or die".
> foreach $line (<IN_FH>){
that should be:
while (my $line = <$in_fh>) {
With:
1. while instead of a foreach - consumes less memory.
2. Lexically scoped $line variable.
3. space before the "{".
> @tmpAR=split(/ /,$line,5); #/ +/ will
> split at any number of white spaces...
Please call the array with a more meaningful name than @tmpAR. Also declare it
using "my" (strict would have warned you about that.).
> next if $tmpAR[$column] == 0;
Where is $column defined? And it should be $column_idx or something.
I personally prefer to label all next/last/redo statements, but some people
here disagree.
> push(@tmpAR2,"$tmpAR[$column] $tmpAR[4]"); # we can use -1 here as
> last element of array
@tmpAR and @tmpAR2? Oh god... Please use more meaningful variable names.
Also, you should use array references here:
[CODE]
push @all_records, [@columns[$column, 4]];
[/CODE]
> }
> print OUT_FH sort { (split(/ /,$a))[0] <=>
> (split(/ /,$b))[0] } @tmpAR2; close IN_FH;
> close OUT_FH;
This could be easier done using the array of array refs and a map to stringify
them.
For more advice, see:
http://perl-begin.org/tutorials/bad-elements/
Sorry for mangling the reply.
Regards,
Shlomi Fish
--
-----------------------------------------------------------------
Shlomi Fish http://www.shlomifish.org/
"Star Trek: We, the Living Dead" - http://shlom.in/st-wtld
Bill Gates, CEO of Microsoft decides to use Richard Stallman’s Emacs as the
basis of his company’s state‐of‐the‐art product Microsoft Editing Macros™
Enterprise Edition XP .NET Professional.
Please reply to list if it's a mailing list post - http://shlom.in/reply .
--
To unsubscribe, e-mail: beginners-unsubscr...@perl.org
For additional commands, e-mail: beginners-h...@perl.org
http://learn.perl.org/
