Gradient Projection Algorithm Rotation for Factor Analysis. See ?GPArotation.Intro for more details.
o Very occassionally (about 1 in 1000 in monte carlo experiments) the algorithm gets stuck and does not improve (so does not converge). The workaround is to restart with a very slightly perturbed starting point.
Changes in GPArotation version 2014.11-1
o Minor format and cleanup required by CRAN checks, no real changes.
Changes in GPArotation version 2012.3-1
o no real changes, but bumping version for new CRAN suitability check.
Changes in GPArotation version 2011.11-1
o updated maintainer email address.
Changes in GPArotation version 2011.10-1
o Modification to vgQ.target to allow NA in target, which is replaced by 0.0 (from William Revelle).
o Added bifactorT and bifactorQ (biquartimin) from William Revelle.
Changes in GPArotation version 2010.07-1
o Fix an error caused by an exact initial setting (from William Revelle).
Changes in GPArotation version 2009.02-2
o Standardized NEWS format for new function news().
Changes in GPArotation version 2009.02-1
o minor documentation corrections as found by a new R-devel.
Changes in GPArotation version 2008.05-1
o added echelon rotation.
o added gradient Gq to result list from GPForth and GPFoblq.
o change license from "GPL-2" to "GPL-2 or later".
Changes in GPArotation version 2007.06-1
o fixed a couple of lingering $Lh (in print and summary methods) that should have been changed to $loadings.
Changes in GPArotation version 2007.04-1
o removed an extra comma in c() that caused a test failure with R-2.5.0
o added eiv rotation.
o renamed $Lh in the result from GPForth and GPFoblq to $loadings. As a result, rotation methods calling these function no longer need to rename this element in order to work with factanal and other programs. (It is a good idea to use the extractor function loadings() rather than refer directly to object structure.)
o changed rotation method functions to return all elements of GPFoblq and GFForth.
o fixed the documentation file primary alias for all rotations (which was being called oblimin).
Changes in GPArotation version 2006.2-2
o extra argument (...) to invisible in print.GPArotation was removed.
Changes in GPArotation version 2006.2-1
o broken references in documentation were fixed and updated.
Changes in GPArotation version 2005.10-1
o warning message about non-convergence expanded to indicate function.
GPArotation version 2005.4-1
o First released version.