Editing Fuzzy set (section)

===Pythagorean fuzzy sets===
One extension of IFS is what is known as Pythagorean fuzzy sets. Such sets satisfy the constraint <math>\mu_A(x)^2 + \nu_A(x)^2 \le 1</math>, which is reminiscent of the Pythagorean theorem.<ref>{{Cite book|last=Yager|first=Ronald R. |title=2013 Joint IFSA World Congress and NAFIPS Annual Meeting (IFSA/NAFIPS) |chapter=Pythagorean fuzzy subsets |date=June 2013 |pages=57–61|doi=10.1109/IFSA-NAFIPS.2013.6608375|isbn=978-1-4799-0348-1|s2cid=36286152}}</ref><ref>{{Cite journal|last=Yager|first=Ronald R|date=2013|title=Pythagorean membership grades in multicriteria decision making|journal=IEEE Transactions on Fuzzy Systems|volume=22|issue=4|pages=958–965|doi=10.1109/TFUZZ.2013.2278989|s2cid=37195356}}</ref><ref>{{Cite book|title=Properties and applications of Pythagorean fuzzy sets.|last=Yager|first=Ronald R.|publisher=Springer |location=Cham|date=December 2015|isbn=978-3-319-26302-1|pages=119–136}}</ref> Pythagorean fuzzy sets can be applicable to real life applications in which the previous condition of <math>\mu_A(x) + \nu_A(x) \le 1</math> is not valid. However, the less restrictive condition of <math>\mu_A(x)^2 + \nu_A(x)^2 \le 1</math> may be suitable in more domains.<ref name="CADsurvey">{{cite journal | vauthors = Yanase J, Triantaphyllou E| title = A Systematic Survey of Computer-Aided Diagnosis in Medicine: Past and Present Developments. | journal = Expert Systems with Applications | volume = 138 | pages = 112821 | date = 2019 | doi = 10.1016/j.eswa.2019.112821 | s2cid = 199019309 }}</ref><ref name="SevenChallenges">{{Cite journal|vauthors = Yanase J, Triantaphyllou E|date=2019|title=The Seven Key Challenges for the Future of Computer-Aided Diagnosis in Medicine.|doi=10.1016/j.ijmedinf.2019.06.017|pmid=31445285|journal= International Journal of Medical Informatics|volume=129|pages=413–422|s2cid=198287435 }}</ref>