Changes in version 1.4.0 (2026-04-27) - Add SH to Hvalid and plot_idx Changes in version 1.3.0 (2025-09-10) - Add methods hclust_ward.D and hclust_war.D2 to all hard CVIs Changes in version 1.2.0 (2025-01-27) - Add Silhouette index Changes in version 1.1.2 (2024-03-31) - Edit the function AccClust. Changes in version 1.1.1 (2024-02-08) - Edit the formula of KWON2 index in both KWON2 and FzzyCVIs. - Edit the function AccClust. Changes in version 1.1.0 (2023-11-08) - Add an argument 'sampling' indicating the undersampling proportion of data to be used. This argument is intended for handling a large dataset. - Fix errors in the manual script files. Changes in version 1.0.1 (2023-10-14) - Update the citation file. - Fix errors in the manual script files. Changes in version 1.0.0 (2023-10-02) - Initial CRAN submission.