# please tell me what this words "eps" do in this instruction.i searched it from eps doc but i don't understand the application here.

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lotus on 24 Mar 2013
Answered: Nikola on 11 Mar 2015
VthL1=-0.25+eps;
VthH1=0.25+eps;

Azzi Abdelmalek on 24 Mar 2013
Edited: Azzi Abdelmalek on 24 Mar 2013
In windows command type
eps
ans =
2.2204e-016eps
eps is a predefined variable
Walter Roberson on 24 Mar 2013
There are three numbers between 0.25 and 0.25+eps, namely 0.25+eps/4, 0.25+2*eps/4, and 0.25+3*eps/4. These can also be written 0.25+eps(0.25), 0.25+2*eps(0.25), and 0.25+3*eps(0.25).
When you see an expression written as (Constant + eps) then often what should have been written is either (Constant + eps(Constant)) or (Constant * (1+eps)) (though the two expressions are not identical if the Constant <= 0)
Suppose you are using a search routine that allows you to provide a lower bound for a value, and it is built in to the search routine that it will allow values that equal that lower bound, but you only want values greater than the lower bound. The trick is to add eps(value) to the value, thus getting "the first representable number greater than the value" as the lower bound that it will actually use.

Nikola on 11 Mar 2015
so if do: find x(x==0)=eps, it will find all values of x that are very close to zero? what about "-eps"? what does that minus sign change?

Nikola on 11 Mar 2015
or it will change all values where x is 0 to very small value?