Circular Data Analysis R package circda version 1.1 Functions to perform maximum likelihood estimation, model-based clustering, discriminant and regression analysis with a circular response variable. The standard textbook for such data is the "Directional Statistics" by Mardia, K. V. and Jupp, P. E. (2000). Other references include: Tsagris M. and Alzeley O. (2025). "Circular and spherical projected Cauchy distributions: A Novel Framework for Circular and Directional Data Modeling". Australian & New Zealand Journal of Statistics, 67(1): 77--103. <doi:10.1111/anzs.12434>. Tsagris M., Papastamoulis P. and Kato S. (2025). "Directional data analysis: spherical Cauchy or Poisson kernel-based distribution". Statistics and Computing, 35:51 <doi:10.1007/s11222-025-10583-0>. Alzeley O. and Tsagris (2026). "On the generalized circular projected Cauchy distribution". Mathematics, 14(11): 1934 <doi:10.3390/math14111934>. Software Depends: R (>= 4.0) Imports: circular, Directional, glmnet, graphics, rangen, Rfast, stats Suggests: Rfast2 Michail Tsagris <mtsagris@uoc.gr> Comprehensive R Archive Network (CRAN) Michail Tsagris [aut, cre] GPL (>= 2) 2026-09-15 application/tgz https://CRAN.R-project.org/package=circda doi:10.32614/CRAN.package.circda