> -----Original Message-----
> From: John W. Krahn [mailto:[EMAIL PROTECTED]
> Sent: Thursday, January 10, 2008 8:26 AM
> To: Perl Beginners
> Subject: Re: open and close a filehandle
>
> Kevin Viel wrote:
> > I have a file with thousands of fields, but a subsequent
> program can
> > only had 3000. I have to break this file up, for simplicity:
> >
> > 00001-03000
> > 03001-06000
> >
> > Hopefully, a basic outline of my code will suffice to get
> informative
> > advice.
> >
> > my $cnt = -1 ;
> > my $subset = 1 ;
> >
> > foreach ( 1..6000 ){
> >
> > $cnt++ ;
> >
> > if ( $cnt = 0 ) {
>
> You are assigning 0 to $cnt so $cnt will always be false and
> the else block will always execute.
Correct, this should be ==, not =.
>
> > $my file = "File_" . $subset ;
> > open CSV , ">" , "$file" ;
> > print CSV "$_[ $_ ]" ;
>
> Why are you using the @_ array? Array indexing starts at 0 but your
> foreach loop starts at 1 so why are you skipping over $_[0]?
An error. The file format is ID, status, SNP1,..., SNPn. ID ($_[ 0 ]) must
appear in each of the subset files.
> > }
> > else{
> > print CSV ",$_[ $_ ]" ;
> > }
> >
> > if ( $cnt == 3000 ){
> > close CSV ;
> > $cnt = 0 ;
> > $subset++ ;
> > }
> >
> > } # cycled through all of the fields
> >
> > After I print the mod( $_ , 3000 ) = 0 field to the file, I
> close that
> > filehandle and reset $cnt to zero. I am not sure, but it
> seems that the
> > open function is not openning the subsequent filehandles.
> >
> > I would appreciate any corrections or suggestions.
>
> I would do something like this:
>
> for my $subset ( 1 .. 2 ) {
> open my $CSV, '>', "File_$subset"
> or die "Cannot open 'File_$subset' $!";
> print $CSV join ',', @_[ ($subset-1)*3000 .. $subset*3000-1 ];
> }
This should greatly improve my program. I will just have to determine how
many subsets and, for the last, the last marker (SNP).
I apologize for the slop. I always use warnings and strict (per Chas's
reply). I code on my Solaris box but e-mail on my windows machine, which
typically has more distractions, and my son was bugging me to leave work...
Thank you,
Kevin
Kevin Viel, PhD
Post-doctoral fellow
Department of Genetics
Southwest Foundation for Biomedical Research
San Antonio, TX 78227
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
http://learn.perl.org/
