Pythagorean theorem

Similarity (geometry)

Image (mathematics)

Physics

Function (biology)

Pattern recognition (psychology)

Artificial intelligence

Trigonometric functions

Acoustics

Geometry

Degree (music)

Cosine similarity

Mathematics

Computer science

Fuzzy set

Membership function

Fuzzy logic

Evolutionary biology

Biology

International Journal of Intelligent Systems

In this paper, we presented 10 similarity measures between Pythagorean fuzzy sets (PFSs) based on the cosine function by considering the degree of membership, degree of nonmembership and degree of hesitation in PFSs. Then, we applied these similarity measures and weighted similarity measures between PFSs to pattern recognition and medical diagnosis. Finally, two illustrative examples are given to demonstrate the efficiency of the similarity measures for pattern recognition and medical diagnosis.

Similarity measures of Pythagorean fuzzy sets based on the cosine function and their applications