Editing Fuzzy logic (section)

====Defuzzification====
{{Main|Defuzzification}}
The goal is to get a continuous variable from fuzzy truth values.<ref>{{cite book|last1=Hájek|first1=Petr|authorlink = Petr Hájek|title=Metamathematics of fuzzy logic|year=1998|publisher=Springer Science & Business Media|edition=4}}</ref><ref name="FuzzyLogic2017">{{cite journal
 | title = Fuzzy Logic
 | author1 = Kaveh Hariri Asli
 | author2 = Soltan Ali Ogli Aliyev
 | author3 = Sabu Thomas
 | author4 = Deepu Gopakumar
 | author5 = Hossein Hariri Asli
 | date = November 2017
 | url = https://www.researchgate.net/publication/363039600
 | journal = ResearchGate
 | access-date = 15 December 2024
}}</ref>

This would be easy if the output truth values were exactly those obtained from fuzzification of a given number.
Since, however, all output truth values are computed independently, in most cases they do not represent such a set of numbers.<ref name="FuzzyLogic2017"></ref>
One has then to decide for a number that matches best the "intention" encoded in the truth value.
For example, for several truth values of fan_speed, an actual speed must be found that best fits the computed truth values of the variables 'slow', 'moderate' and so on.<ref name="FuzzyLogic2017"></ref>

There is no single algorithm for this purpose.

A common algorithm is
# For each truth value, cut the membership function at this value
# Combine the resulting curves using the OR operator
# Find the center-of-weight of the area under the curve
# The x position of this center is then the final output.