Changes in version 1.1.0                        

Major changes

  - Added projection SPCA (method = "pspca"), including a new C++
    implementation.
  - Added a dedicated C++ backend for fat matrices, where the number of
    variables exceeds the number of observations.
  - Redesigned the C++ tall-matrix engine for improved speed, memory
    use, and maintainability.
  - Refactored the C++ codebase so large objects are passed by reference
    where appropriate.
  - Added try/catch wrappers around the main C++ entry points to improve
    error reporting from compiled code.

R interface

  - Reworked the main spca() interface while preserving the core LS-SPCA
    workflow.
  - Rewrote plot.spca() with improved bar plots, circular plots, heat
    maps, grouping support, and plotting controls.
  - Rewrote new_spca() to make externally computed sparse loading
    matrices easier to store and inspect as spca objects.
  - Improved printing and summary methods for spca objects.
  - Improved comparison tools for multiple sparse PCA fits.
  - Added or revised helper functions for grouped summaries,
    diagnostics, and validation.

Reliability and testing

  - Added a testthat test suite.
  - Fixed multiple issues in the R interface and C++ backend.
  - Improved input validation and error messages.
  - Fixed edge cases affecting sparse loadings, component summaries, and
    variance-explained diagnostics.

Documentation

  - Rewrote and expanded the package documentation.
  - Rewrote the vignettes for the revamped package.
  - Updated examples to reflect the current interface and available
    LS-SPCA methods.
  - Added documentation for projection SPCA and the tall/fat backend
    distinction.

                        Changes in version 1.0.0                        

Major rewrite

  - First full release of the revamped spca package.
  - Replaced the previous computational core with a new C++ backend.
  - Added separate computational paths for tall and fat data matrices.
  - Added projection SPCA as a new LS-SPCA method.
  - Updated the package interface to support the redesigned backend.

Package structure

  - Reorganized internal R and C++ code.
  - Improved consistency of returned spca objects.
  - Updated exported functions and methods to use a common object
    structure.
  - Added tests and revised examples for the new implementation.

                        Changes in version 0.9.0                        

Development release

  - Introduced the new C++ tall-matrix engine.
  - Began migration of computational routines from the earlier
    implementation to the redesigned backend.
  - Added preliminary support for projection SPCA.
  - Improved memory handling in compiled code.
  - Updated internal validation routines.

                        Changes in version 0.8.0                        

Development release

  - Reworked plotting methods for spca objects.
  - Added improved graphical comparison of loadings and contributions.
  - Added support for grouped variables in summaries and plots.
  - Revised helper functions used by examples and vignettes.
  - Improved documentation of sparse loadings, contributions, VEXP,
    CVEXP, and component correlations.

                        Changes in version 0.7.0                        

Development release

  - Began the package revamp following version 0.6.0.
  - Reorganized the R interface around fitted spca objects.
  - Improved print and summary output.
  - Added early validation and diagnostic improvements.
  - Fixed several bugs from the previous CRAN release.

                 Changes in version 0.6.0 (2014-12-16)                  

  - Previous CRAN release.