Please tell me about Iteration, and give an example how to use it.
thanks

I'm no expert, for what it's worth, the way I understand it, an
iteration, is an execution of a formula or process, or one cycle. I use
it to prevent circular reference errors. I set the iteration level to
one. I can't think of another use for it unless you could apply a
variable to the iteration setting.


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M. Homayon wrote:
Please tell me about Iteration, and give an example how to use it.
thanks

----------------

If you mean as a general programming technique, iteration is to do something
over and over. As a trivial example you might add up a list of 10 array
elements as follows:

Sum = 0
for I = 1 to 10
Sum = Sum + Data(I)
next I

Programs are generally chock full of iterative loops to do things. You don't
want to write a million lines of code to do something a million times if you can
avoid it.

Bill

As noted, iteration is kind of a broad topic. One way it is used in
math is to find the roots of equations (ie given y=f(x) what value(s)
of x cause y=0). Several different algorithms out there
(Newton-Raphson, secant, bisection, etc. any decent numerical methods
text should describe). Basically the idea is to "guess" at the root,
then, from information in the function, make a second (hopefully
better) guess and continue iterating until the algorithm converges to
an answer. Such methods aren't foolproof; there are cases where a
given algorithm will fail to converge, or converge to the wrong answer,
or diverge. Properly understood and applied, numerical methods
represent a good way of solving problems for which no analytic solution
exists.


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