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Variable names like i and j - why?

Q: Why do people use variable names like "i" and "j" for loop counters? I thought that you were supposed to use longer, desciptive names!

A1: Fortran (FORmula TRANslator) was one of the prevalent programming languages in the 1960s and 1970s, at a time when many programming techniques, algorithms and methodologies were being developed, and in Fortran, variable names starting with I J K L M and N were implicitly integer, and all others (A to H and O to Z) implied float. So it was natural to START your loop variables - which tended to be integers as they counted up through discrete array members - with one of these default letters.

A2: Loop variables are set up and used within a very restricted (small) area of your program, but are intensively referred to within that area. Giving them a long name which you have to keep repeating leads to code that's needlessly stretched and can actually be more confusing that shorter code. Think about it ... in the wider real, we refer to our queen as "Elizabeth" but I'll bet that in the small local environment of home at Windsor   Sandringham   Balmoral Buck House, her Phil calls her Betty or even Bee.
(written 2009-09-22)

 
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
J608 - Java - Naming Conventions and Code Management
  [2604] Tips for writing a test program (Ruby / Python / Java) - (2010-01-29)

Q101 - Object Orientation and General technical topics - Programming Principles
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  [4632] Remember to ask the question before you listen for the answer - (2016-01-26)
  [4611] Hungarian, Camel, Snake and Kebab - variable naming conventions - (2016-01-03)
  [4325] Learning to program - what are algorithms and design patterns? - (2014-11-22)
  [4206] Writing the perfect program in Tcl? - (2013-11-13)
  [4153] Rooms available tonight - how to code an algorithm from first principles - (2013-08-19)
  [4118] We not only teach PHP and Python - we teach good PHP and Python Practice! - (2013-06-18)
  [4090] Test Driven Development in Python - Customer Comes First - (2013-05-16)
  [4061] Seamless, integrated IT - we have a long way to go! - (2013-04-11)
  [4003] Web and console - same principle, same code - Ruby example - (2013-02-14)
  [3954] Lesson 1 in programing - write clean, reuseable and maintainable tidy code - (2012-12-16)
  [3928] Storing your intermediate data - what format should you you choose? - (2012-11-20)
  [3878] From Structured to Object Oriented Programming. - (2012-10-02)
  [3673] Object oriented or structured - a comparison in Python. Also writing clean regular expressions - (2012-03-26)
  [3551] Some terms used in programming (Biased towards Python) - (2011-12-12)
  [3548] Dark mornings, dog update, and Python and Lua courses before Christmas - (2011-12-10)
  [3542] What order are operations performed in, in a Perl expression? - (2011-12-07)
  [3456] Stepping stones - early coding, and writing re-usable code quickly - (2011-09-24)
  [3026] Coding efficiency - do not repeat yourself! - (2010-11-02)
  [2964] An introduction to file handling in programs - buffering, standard in and out, and file handles - (2010-09-21)
  [2915] Looking up a value by key - associative arrays / Hashes / Dictionaries - (2010-08-11)
  [2878] Program for reliability and efficiency - do not duplicate, but rather share and re-use - (2010-07-19)
  [2769] Easy - but for whom? - (2010-05-18)
  [2737] Improving your function calls (APIs) - General and PHP - (2010-04-24)
  [2586] And and Or illustrated by locks - (2010-01-17)
  [2550] Do not copy and paste code - there are much better ways - (2009-12-26)
  [2510] The music of the stock market - (2009-11-22)
  [2327] Planning! - (2009-08-08)
  [2310] Learning to write high quality code in Lua - (2009-07-30)
  [2228] Where do I start when writing a program? - (2009-06-11)
  [2022] Pre and post increment - the ++ operator - (2009-02-03)
  [2001] I have not programmed before, and need to learn - (2009-01-19)


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