Nothing
One can easily draw the membership function of f(x,y) by package 'FuzzyNumbers.Ext.2' in which f(.,.) is supposed monotone and x and y are two fuzzy numbers. This work is possible using function f2apply() which is an extension of function fapply() from Package 'FuzzyNumbers' for twovariable monotone functions. Moreover, this package has the ability of computing the core, support and alphacuts of the fuzzyvalued final result.
Package details 


Author  Abbas Parchami (Department of Statistics, Faculty of Mathematics and Computer, Shahid Bahonar University of Kerman, Kerman, Iran) 
Maintainer  Abbas Parchami <parchami@uk.ac.ir> 
License  LGPL (>= 3) 
Version  3.2 
Package repository  View on CRAN 
Installation 
Install the latest version of this package by entering the following in R:

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