NEWS

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IFFuzzyStats 0.1.0 (2026-10-21)

Initial CRAN release

• ifv() S3 class for intuitionistic fuzzy values (membership mu, non-membership nu, hesitation pi = 1 - mu - nu), with as_ifv(), is_ifv(), if_pi(), if_check() and if_comp() helpers.
• Xu (2007) arithmetic: if_add(), if_mul(), if_scalar_mul(), if_pow(), plus Einstein variants if_einstein_add(), if_einstein_mul(), if_einstein_scalar_mul(), if_einstein_pow().
• Aggregation operators: ifwa(), ifwg(), ifowa(), ifowg(), ifha(), ifhg(), if_einstein_wa(), if_einstein_wg() and the if_aggregate_matrix() decision-matrix helper.
• Score / accuracy / ranking: if_score(), if_accuracy(), if_hesitation(), if_rank(), if_order(), if_best().
• Entropy measures: if_entropy() with "burillo", "szmidt", "vlachos" and "zeng_li" methods.
• Distances: if_dist() with "hamming", "euclidean", "hausdorff", "ye", "ye_cosine" and "park" methods (optional element weights).
• Similarities: if_sim() with "chen", "hong_kim", "ye_cosine", "ye_weighted", "deng"/"liang_shi" (Jaccard) and "dice" methods.
• Approximate reasoning: max-min / max-product if_compose(), if_infer() (compositional rule of inference) and if_rule_block().
• Clustering: intuitionistic fuzzy c-means ifcmeans() (with hesitation penalty lambda and nstart random starts) and hard ifkmeans().
• Decision making: IF-TOPSIS if_topsis() (Boran et al. 2009) and the if_rank_df() ranking table.
• Converters: if_fuzzify() (numeric to IFV) and if_defuzzify() ("score", "expected", "accuracy", "mu").
• Vignette IFFuzzyStats-intro, full testthat suite, base-R only (no hard dependencies).