for(int i=0; i<size; i++)

[DerekT P]

It was also a feature of some early BASIC implementations. There were 26 variables available; A through H were floating point, I through P (??) were integers; R(??) through Z were also floating point. The only explicit type declarations were to suffix one of the single-letter variables with the $ symbol to indicate string. "I" was commonly used for loop control as being the first integer variable. It's a habit I learned in the 1960s and I still use it (very occasionally). Old habits die hard...

[Bikash Prakash Dash]

while(life!=death) { age++; research++; development++; }

[The Nightcoder]

Hi, Others have said this, but it deserves to be repeated: This is classical math (handwritten, typed or printed), from a couple of centuries before the advent of computers. It's pretty natural that it was adopted by most mathematically-oriented computer languages (and, consequently, by later languages), and it also explains why it feels natural to most programmers (who have read any math - which should be a reasonable expectation) even today. indices: i, j, k (don't remember how it goes on after that quantities: n, m (then p, q if I remember correctly - o can be confusing). dimensions: x, y, z, t, (xi), (eta), (theta). I don't remember what happens when we run out of letters for indices and quantities, but if I remember correctly these sequences also continue with greek letters. So:

for (i = 0; i < n; i++)
{
for (j = 0; j < m; i++)
{
for (k = 0; k < p; k++)
{
}
}
}

Pretty straightforward. And Newton would have understood it without thinking... :)

Peter the small turnip (1) It Has To Work. --RFC 1925[^]

[Lutoslaw]

AspDotNetDev wrote:

From this, we can ascertain the correct letters to use for each new level of loop nesting: ijklouhmpygntfbrdvescwaxqz.

How deep did you go into the spiral? I usually stop on the 'g'.

Greetings - Jacek

[AspDotNetDev]

I've never had a need to go past "c".

Thou mewling ill-breeding pignut!

[Lutoslaw]

You should be women, and yet your beards forbid me to interpret that you are so.[^]. Awesome.

Greetings - Jacek

[John Hunley]

I personally use x (and y and z for nested loops - if you nest more than two levels, you need to redesign), I make it unsigned (unless there's a specific reason to use signed) because that more accurately models the real world, and I use the prefix form of the increment operator because it's potentially more efficient. So my canonical form of that construct would be:

for (unsigned x = 0; x < size; ++x)

And yes, some of my co-workers make fun of me. The ones who spend twice as much time debugging their code as I do debugging mine.

[MacSpudster]

I use

for (int r = 0; r < size; i++)

because 1) "r" is directly next to "t" when I type "int_[spaceBar]_r", typing flow is much nicer; 2) "r" is on my left-hand vs. the right-hand, so when I type "someArray[r]" I type faster as my fingers type in sync with one another; seriously, try it for a week and you'll see it flows much better; 3) "r" means "repeat" (or "record") in my brain 4) using i reminds me of when I flunked Spanish... example: iFlunked! 5) I got sick of iThisCrap, iThatCrap, iWTF; .... - even though I actually originated using "i[SomeWord]" during my Apple dayz ... yes, iCreatedThisMess ... r u kidding me? no, i am not!

[mc42]

Since I, j, k, l are int by default, a variable named God would, by default, be a 'real' number - ie, floating point. You'd have to declare the variable God to be an integer in order for it to be taken that way. Yes, this is probably a good candidate for the most delayed response ever.

[Rob Grainger]

mc42 wrote:

Yes, this is probably a good candidate for the most delayed response ever.

It did take me a while to get the context there. Thanks for explaining. It does tickle me that an Imaginary being defaults to Real, while i is definitely not imaginary. Mathematicians would shudder. (Edited for grammar)

"If you don't fail at least 90 percent of the time, you're not aiming high enough." Alan Kay.