I think the message means $worksheet is undefined, not one of the parameters.

And I think the real problem is because of all the extra my's in there.

my $workbook;     # No need for the = ()
my $worksheet;    # No need for the = ()
# Create output file with user filename:
if ($outfile ne "d") {
  $workbook = Spreadsheet::WriteExcel->new($outfile);  # No my, or $wo
+rkbook will go out of scope at the end of the if block
  $worksheet = $workbook->add_worksheet(); # same here
  print "What should we label the column containing the data?\n";
  my $colname = <STDIN>;
  chomp($colname);
  $worksheet->write(0,"A",$colname); 
}

# Other code here I assume

# Write 00 temperature data into file:
$read = 4+(($day-1)*58);
$temp = $xls->1{("B", $read)};
$row = $day + 1;
$worksheet->write($row,$col,$temp); # No my
$day = $day + 1;

[download]

Now $worksheet won't go out of scope after the if block, and the later code can still use it.

In reply to Re^2: Issue with Spreadsheet::WriteExcel by Crackers2
in thread Issue with Spreadsheet::WriteExcel by mprogan365

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