Re: Get excel column letter from number

What's the maximum for column numbers? A simple routine for up to three letters:

sub ltr { ("A".."ZZZ")[@_] }

print ltr(26);
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Comment on Re: Get excel column letter from number Download Code

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Re^2: Get excel column letter from number by duelafn (Parson) on Jul 26, 2016 at 13:10 UTC
Simple and elegant given that Excel has a max column of "XFD". I'd modify this to cache the column names and throw a fit if we go too far (eventually, the column cap will be increased or removed): `sub ltr_cached { state $ltr_cache = ["A".."ZZZ"]; return ($$ltr_cache[$_[0]] or die "column too big: $_[0]") }` [download] Good Day, Dean	[reply] [d/l]
Re^2: Get excel column letter from number by pryrt (Abbot) on Jul 26, 2016 at 13:32 UTC
For simplicity and perlness points, an extra ++ to this one... :-) Running haukex's test-and-benchmark with AM's `ltr()` included (without 285075=>'PERL' in the test list), `ltr()` appears about 10x more efficient than `colname()`. A four-Z-based `ltr()`, however, is about 75% less efficient than `colname()`. Excel 2007 upped the limit from 2-letter/256-column to 3-letter/16384-column, and that hasn't changed as of Excel 2016, so the more-efficient ZZZ-based `ltr()` is sufficient for now. :-)	[reply] [d/l] [select]