Question

i've only just started this course guys and im trying to understand what "Epsilon" is or means ??.

Answer 1

Well, as a term, let me look at that first. In mathematics there is a concept of how close is close enough when dealing with the definition of a limit. This is called the epsilon-delta definition of limit. That is where they got the term epsilon from.

How they are using it is for the question of how close to a real root do you need to get before you call your decimal answer good? You and I know the square root of 4 is 2. But what about a computer guessing at it? Is 1.9 close enough? Is 1.99? 1.999999? 2.000001? What is close enough for you to call it a "good" answer? That is the epsilon they mean.

Answer 2

Oh, and the concept of good is in quotes because there are many goods. Good for say high precision mathematics without time as a factor could be let the computer keep working for hours and hours until you get a really long a precise value. On the other hand, good for a calculator is going to be something that takes a fraction of a second to compute and only needs to be to eight or ten places.

Answer 3

yeah, I think it just refers to what you consider to be an acceptable plus or minus value for an answer.

Answer 4

@egecas That is a good way to sum it up. I was just going into why they chose it.