why i

[Ben Finney]

On Tue, 25 May 2004 15:44:25 GMT, Dennis Lee Bieber wrote:
> On 25 May 2004 16:35:29 +0950, Ben Finney wrote:
>> The usage of "i" was promulgated by the FORTRAN language, which
>> allowed only single-letter variable names (and was all upper case,
>
> That must have been a really old version of FORTRAN -- all versions
> I've encountered allowed for, at least, 6 significant characters in
> variable names. (This goes back to F-IV/F-66). BASIC was limited to
> one or two characters.

Yes, I've since been corrected; FORTRAN allowed at least 6 characters
for variable names.

I was confused by my memory of the "I through N" rule of FORTRAN's
integer/real split; for some reason that translated into erroneously
thinking the variables were only one character in length.

I'm in agreement with others that FORTRAN was, in this regard, influeced
by the existing mathematical formula convention of 'i', 'j', 'k' etc.
for vector subscripts.  Since FORTRAN, as the language name indicates,
was initially used for mathematical formula algorithms, the use of a FOR
loop to iterate through a vector (or array) was common, and thus using
the variable I for the index would seem natural to a
mathematically-oriented programmer.

-- 
 \           "There is no reason anyone would want a computer in their |
  `\          home."  -- Ken Olson, president, chairman and founder of |
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Ben Finney <http://bignose.squidly.org/>