Where does L come from?
On 08/25/2018 04:33 PM, Duncan Murdoch wrote:
On 25/08/2018 4:49 PM, Herv? Pag?s wrote:
The choice of the L suffix in R to mean "R integer type", which is mapped to the "int" type at the C level, and NOT to the "long int" type, is really unfortunate as it seems to be misleading and confusing a lot of people.
I don't have stats about this so I take back the "lot".
Can you provide any evidence of that (e.g. a link to a message from one of these people)?? I think a lot of people don't really know about the L suffix, but that's different from being confused or misleaded by it. And if you make a criticism like that, it would really be fair to suggest what R should have done instead.? I can't think of anything better, given that "i" was already taken, and that the lack of a decimal place had historically not been significant.? Using "I" *would* have been confusing (3i versus 3I being very different).? Deciding that 3 suddenly became an integer value different from 3. would have led to lots of inefficient conversions (since stats mainly deals with floating point values).
Maybe 10N, or 10n? I'm not convinced that 10I would have been confusing but the I can easily be mistaken for a 1. H.
Duncan Murdoch
The fact that nowadays "int" and "long int" have the same size on most platforms is only anecdotal here. Just my 2 cents. H. On 08/25/2018 10:01 AM, Dirk Eddelbuettel wrote:
On 25 August 2018 at 09:28, Carl Boettiger wrote: | I always thought it meant "Long" (I'm assuming R's integers are long | integers in C sense (iirrc one can declare 'long x', and it being common to | refer to integers as "longs"? in the same way we use "doubles" to mean | double precision floating point).? But pure speculation on my part, so I'm | curious! It does per my copy (dated 1990 !!) of the 2nd ed of Kernighan & Ritchie.? It explicitly mentions (sec 2.2) that 'int' may be 16 or 32 bits, and 'long' is 32 bit; and (in sec 2.3) introduces the I, U, and L labels for constants.? So "back then when" 32 bit was indeed long.? And as R uses 32 bit integers ... (It is all murky because the size is an implementation detail and later "essentially everybody" moved to 32 bit integers and 64 bit longs as the 64 bit architectures became prevalent.? Which is why when it matters one should really use more explicit types like int32_t or int64_t.) Dirk
Herv? Pag?s Program in Computational Biology Division of Public Health Sciences Fred Hutchinson Cancer Research Center 1100 Fairview Ave. N, M1-B514 P.O. Box 19024 Seattle, WA 98109-1024 E-mail: hpages at fredhutch.org Phone: (206) 667-5791 Fax: (206) 667-1319