NEWS
squat 0.5.0.9000
squat 0.5.0 (2026-01-15)
New features
Add QTS transformations into:
- smooth representation using b-spline smoothing curves;
- angular velocity vector and magnitude;
- angular acceleration vector and magnitude.
Minor improvements and bug fixes
- Skip tests using gghightlight if not installed;
- Some documentation updates;
- Updates of GitHub action workflows.
squat 0.4.0 (2025-05-20)
New features
- Adaptation to new API of fdacluster.
- Added rotation invariant elastic distance.
- Added no alignment option in distance matrix computation via SRVF.
- Added roll-pitch-yaw representation.
- Added
format()/print() pair correctly.
Minor improvements and bug fixes
- Remove dependency to purrr in favor of base R
*apply() family to reduce
dependency trail.
- Replace furrr with future.apply for consistency with the removal of
purrr.
- Update roxygen version.
- Fix bug in predict from PCA with new data. Properly compute L2 inner product.
- Fix bug in predict from prcomp object.
squat 0.3.0 (2024-01-10)
New features
- Added
S3 specialization of the stats::predict() function for prcomp_qts
objects.
- Added function
qts2aats() which allows to switch from quaternion to
axis-angle representation of rotations.
- Added usual operations
+, -, * and inverse_qts() for quaternion time
series using the Eigen
library.
Small improvements
- Make sure quaternion geodesic mean is not flipped.
- Fix issues in PCA:
- avoid numerical overflows due to bad choice of
k in gam();
- improved documentation;
- Use same number of basis functions in uni- and multivariate decompositions.
- Updated GHA scripts and
README.
- Fix bug related to Rcpp following RcppCore/Rcpp#1287.
squat 0.2.1 (2023-07-09)
- Add
use_fence robustification option;
- Adapt to changes in fdacluster;
- Properly compute tangent spaces along mean QTS;
- Update News section of website.
squat 0.2.0 (2023-06-04)
Major features:
- Added hierarichal clustering;
- Added DBSCAN clustering;
- Added distance matrix computation.
Minor improvements:
- Adapted code to match new API in fdacluster package.
squat 0.1.0 (2022-12-22)
Major statistical features
- A first API proposal with a class
qts and a class qts_sample for which a
number of methods are properly implemented.
- Available statistical methods for QTS samples:
- random generation according to the Gaussian functional model via
rnorm_qts(),
scale(),
mean(),
median(),
- distance matrix computation via
distDTW() (i.e. for now we use the dynamic time warping),
- tangent principal component analysis via
prcomp(),
- k-means with optional alignment via
kmeans().
- Added multiple ways of displaying samples of QTS.
- Added two example datasets.
Improvements
- Make all functions applicable to a single QTS also applicable to QTS samples,
with appropriate class for the output.
- Enable
as_qts_sample() to generate a QTS sample of size 1 from a single QTS
as input argument.
- Rename
change_points argument to the plot.qts() function to better reflect
its flexibility.
- Added subset operator for QTS sample objects.
- Added
append S3 method for QTS sample objects.
- Added
hemispherize() function to remove any discontinuities in QTS due to
quaternion flips.
- Any parallelization computation is now handled using the
futureverse principles and, in particular,
implemented through the use of the furrr
package.
squat 0.0.1 (2022-09-27)
- Added a
NEWS.md file to track changes to the package.
- Initial version.