lfl 2.3.1

• released: 2025-12-16
• removed C++11 requirement as R already supports higher C++ standards
• updated autoconfig files
• polished documentation

lfl 2.3.0

• released: 2025-06-27
• implemented str.fsets(), as_tibble.fsets()
• removed dependency on the zoo package
• added lowerBound() algebra for missing values

lfl 2.2.1

• released: 2024-10-22
• implemented the experimental Center of Gravity defuzzification method (defuzz())
• added “a few” and “several” fuzzy quantifiers to the quantifier() function

lfl 2.2.0

• released: 2022-09-08
• added equidist(), equifreq()
• added function to compute fuzzy-transform (ft()) and its inverse (ftinv())
• parallel t-norms and t-conorms rewritten in C++

lfl 2.1.2

• released: 2021-08-23
• added vignette

lfl 2.1.1

• released: 2020-11-04
• fixed the minimum required version of R to 3.6

lfl 2.1.0

• released: 2020-10-15
• the result of algebra() is now an S3 class, implemented print.algebra()
• added involutive negation to algebra()$ni
• added nelson(), lowerEst() handlers of NA for algebra()
• added print() method for linguistic contexts
• added negated=FALSE argument to the lingexpr() function
• implemented bi-residuum of the dragonfly algebra
• implemented order operation of the dragonfly and lowerEst algebras
• added sugeno()
• added fuzzy quantifiers
• deprecated some arguments of the compose() function
• removed deprecated functions: lcut3(), lcut5()

lfl 2.0.1

• released: 2020-05-19
• added support for percentual quantifiers in compose()
• documentation spell-check