######################################################################
# 7/25/2016
# In: Column index, 0-n.
# Out: Letter(s) representing column in Excel. 0=A, 1=B, 25=Z, 26=AA...
# 
# Inspired by http://stackoverflow.com/questions/3302857/algorithm-to-get-the-excel-like-column-name-of-a-number
# 7/25/2016 WORKS!
sub excelpos2ltr
{my($oldcol)=@_; # Col starts at 0='A'
my($procname,$numeric,$ltr,$num2,$outs);

$procname="excelpos2ltr";

# Alt method 4.
$numeric = $oldcol % 26;
$ltr = chr(65 + $numeric);
#$num2 = intval($oldcol / 26); # old line
$num2 = int($oldcol / 26);
if ($num2 > 0)
    {
    $outs=excelpos2ltr($num2 - 1) . $ltr;
    }
else
    {
    $outs=$ltr;
    }
return $outs;
}