It's lunch time, I'm bored. Something like this should work .

#!perl.exe

use Modern::Perl; #or use strict;use warnings;
use Spreadsheet::WriteExcel;

my $input_fn = 'perlmonks.org.918502.txt'; # or the name of your file
my $output_fn = 'perlmonks.org.918502.xls'; # or the name of the xls f
+ile you want to produce

#open the input for reading
open my $input_fh, '<', $input_fn or die "Unable to open $input_fn: $1
+\n";

#open xls file for output
my $workbook = Spreadsheet::WriteExcel->new($output_fn);
die "Problems creating Excel file: $!\n" unless defined $workbook;

#create a worksheet with the name of the input file
my $worksheet = $workbook->add_worksheet($input_fn);

#split the line, and write to the matching row in the spreadsheet
while (my $line = <$input_fh>) {
    $line =~ /(\d+).{5}(\d+.\d+)\s(\d+.\d+)\s(\d+.\d+)/;
    my @columns = ($2, $3, $4);
    $worksheet->write_row($1,0,\@columns);
}
[download]

Or Excel::Writer::XLSX if you have the latest version of MS Excel and you want to write in it's native XML format.

You might want to do this go get around the limitations in the older Excel format (eg: maximum of 256 columns and 2**16 rows per sheet).

Both modules are written by the same author and claim to have the same interface, so you could decide which to use at runtime while only having a few lines of code that depend on which file format you plan to write.

The easiest thing (in my opinion) is to use a comma-separated-values format, and import into Excel.

open INPUT, "<./input.txt"; # assuming that's your input
open OUTPUT, ">./output.csv"; # comma-separated-values output
print OUTPUT "First column heading,Second column heading,Third column 
+heading\n";
while (<INPUT>) {
  my $first = s/(\d+)\.+//;
  my @others = split /\s\+/;
  print OUTPUT join(',' ($first, @others)).$/;
}
[download]

If you're going to take this approach, you'll probably be better of looking at Text::CSV unless you can be 100% sure that your input will never contain any commas.

Does every line have to be put in a separate cell? How to split each row? What to do with 1.....2.34: is this one cell or multiple cells?

The various Spreadsheet modules on CPAN will be a good place to start.

I agree that the easiest way is a comma separated file with the extension csv. Excel will open this up when you double click on the file.

If your data has commas in it, you could change the separator to a pipe, but then you would have to do a data import into excel and specify the separator which is a little bit more work

You might be better with tab / \t as excel will load that with a .csv extension as well.