# necessityStrictUndervaluation: Necessity of strict undervaluation In FuzzyNumbers: Tools to Deal with Fuzzy Numbers

## Description

Determines value of necessity of e1<e2, the result is from range [0,1]. Value 0 indicates no fulfilment of the operator and 1 indicates complete fulfilment.

## Usage

 ```1 2 3``` ```## S4 method for signature ## 'PiecewiseLinearFuzzyNumber,PiecewiseLinearFuzzyNumber' necessityStrictUndervaluation(e1, e2) ```

## Arguments

 `e1` a PiecewiseLinearFuzzyNumber `e2` a PiecewiseLinearFuzzyNumber

## Value

Returns a value from range [0,1] indicating the necessity of exceedance of e2 by e1.

## References

DUBOIS, Didier and PRADE, Henri, 1983, Ranking Fuzzy Numbers in the Setting of Possibility Theory. Information Sciences. 1983. Vol. 30, no. 3, p. 183–224.

Other comparison-operators: `necessityExceedance()`, `necessityStrictExceedance()`, `necessityUndervaluation()`, `possibilityExceedance()`, `possibilityStrictExceedance()`, `possibilityStrictUndervaluation()`, `possibilityUndervaluation()`

Other PiecewiseLinearFuzzyNumber-method: `Arithmetic`, `Extract`, `PiecewiseLinearFuzzyNumber-class`, `PiecewiseLinearFuzzyNumber`, `^,PiecewiseLinearFuzzyNumber,numeric-method`, `alphaInterval()`, `arctan2()`, `as.PiecewiseLinearFuzzyNumber()`, `as.PowerFuzzyNumber()`, `as.TrapezoidalFuzzyNumber()`, `as.character()`, `expectedInterval()`, `fapply()`, `maximum()`, `minimum()`, `necessityExceedance()`, `necessityStrictExceedance()`, `necessityUndervaluation()`, `plot()`, `possibilityExceedance()`, `possibilityStrictExceedance()`, `possibilityStrictUndervaluation()`, `possibilityUndervaluation()`

## Examples

 ```1 2 3 4 5``` ```a <- TriangularFuzzyNumber(0.2, 1.0, 2.8) b <- TriangularFuzzyNumber(0, 1.8, 2.2) a <- as.PiecewiseLinearFuzzyNumber(a, knot.n = 9) b <- as.PiecewiseLinearFuzzyNumber(b, knot.n = 9) necessityStrictUndervaluation(a,b) ```

### Example output

```[1] 0.2222222
```

FuzzyNumbers documentation built on Nov. 15, 2021, 5:09 p.m.