cec() now accepts an optional weights argument: a numeric vector of non-negative values, one per observation. Cluster means, covariances, and the returned $probability field are all weight-aware. When weights = NULL (default), behaviour is identical to previous versions.
Breaking changes
When weights is non-uniform, $probability now reports the weighted mixing proportion W_k / W_total rather than the observation-count fraction n_k / m.
When weights is non-uniform, card.min is now interpreted as a minimum weight sum rather than a minimum observation count.
Minor improvements and fixes
Fixed a crash with non-uniform weights: a cluster with fewer observations than dimensions could pass the weight-sum-based card.min check and produce a singular covariance. Cluster removal now also enforces a minimum observation count.
Fixed a crash in cec(..., keep.removed = TRUE) whenever a cluster was actually removed during clustering (Error in matrix(NA, 1, ncol(center)) : non-numeric matrix extent).
plot.cec() now warns and skips a single cluster’s covariance ellipse if it cannot be drawn (e.g. a degenerate covariance), instead of failing the whole plot. Previously the surrounding tryCatch had no error handler and so provided no protection.
Error messages for internal clustering failures now include the underlying cause instead of a generic message.
Fixed a C++20 compiler warning (ambiguous reversed comparison operators) flagged by CRAN’s macOS checks.
CEC v0.11.3
CRAN release: 2026-02-04
New features
N/A.
Minor improvements and fixes
Fixing typo in Makevars.
CEC v0.11.2
CRAN release: 2024-10-10
New features
N/A.
Minor improvements and fixes
Fixing CRAN NO_REMAP error with R > 4.5.0.
CEC v0.11.1
CRAN release: 2024-01-08
New features
N/A.
Minor improvements and fixes
Fixing new CRAN check errors.
CEC v0.11.0
CRAN release: 2022-12-13
New features
New maintainer.
New logo.
Minor improvements and fixes
Refactoring/reorganizing R code for easier maintenance.
Improving of documentation.
Moving to GitHub actions for CI instead of Travis.
CEC v0.10.3
CRAN release: 2021-09-21
New features
N/A.
Minor improvements and fixes
Fixing gcc-11 issues.
Fixing other CRAN issues.
CEC v0.10.2
CRAN release: 2018-07-26
New features
Adding fixed mean model.
Adding data set: threeGaussians.
Minor improvements and fixes
Fixing compilation issues on some platforms.
CEC v0.10.1
CRAN release: 2018-07-09
New features
Rewriting all C the code in C++11.
Adding split method.
Adding threads.
Minor improvements and fixes
N/A.
CEC v0.9.4
CRAN release: 2016-04-24
New features
N/A.
Minor improvements and fixes
Adding README.md.
Lots of refactoring.
Small fixes.
CEC v0.9.3
CRAN release: 2015-02-03
New features
Changing the way initial centers vector is handled: for each start, length(centers) clusterings are performed.
Adding two datasets: fourGaussians and mixShapes.
Minor improvements and fixes
Giving up support of -1 iterations (fixing memcheck problems).
CEC v0.9.2
CRAN release: 2014-11-15
New features
N/A
Minor improvements and fixes
Checking input data for NA values (session crushing).
