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 2013-3-24

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回答： Nikola 2015-3-11

                                                                        VthL1=-0.25+eps;
VthH1=0.25+eps;

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Azzi Abdelmalek 2013-3-24

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编辑：Azzi Abdelmalek 2013-3-24

在 MATLAB Online 中打开

In windows command type

eps
ans =
2.2204e-016eps

eps is a predefined variable

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lotus 2013-3-24

i got it.thanks

Walter Roberson 2013-3-24

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.

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