Change log for package SOAs Version 1.4, 10 August 2023 * modified Spattern calculations to use full factorial based coding instead of the power coding, because this is faster and also works for non-prime and non-prime-power s * bug fix to Spattern: For a few cases, an individual weight for a main effect column was too large with the old calculation method, e.g. for column 124 with s=5, the weight was 4 instead of 3, due to numeric glitches (ceiling(log(124+1, base=5)) is 4). * removed iterators and itertools from imports field of DESCRIPTION * excluded documentation of internal function levels.no, and added an error message for the unlikely event that someone attempts to call base::levels on an object of class no Version 1.3, 03 October 2022 * implemented the stratification pattern that was proposed by Tian and Xu (2022) and whose implementation is described in Groemping (2022b) (important functions: Spattern and dim_wt_tab; important supporting function: contr.Power yields contrasts for factors with s^el levels) Version 1.2, 05 August 2022 * modified function createAB and documentation in SOAs2plus_regular: the He, Cheng and Tang (2018) strength 2+ SOAs now have orthogonal columns more often, because the columns for matrix B are selected from all columns that are not used for A (instead of only the columns that were not eligible for A). Users who need the previous behavior for reproducing a design from earlier package versions can use the argument old. * sped up the selection of columns for matrix B in case orthogonal columns are requested (work directly with coefficient matrix instead of using function length3 from package DoE.base) * added an internal function createAB_fast for SOAs2plus_regular: this bypasses orthogonality requests in order to obtain a fast solution or to forsake orthogonality in the hope of improved space-filling (argument orth) Version 1.1, 04 June 2022 * added functions guide_SOAs and guide_SOAs_from_OA for providing guidance about implemented SOA constructions * various improvements of documentation, and update of references * BcolsFromBcolllist: changed vertex attributes to FALSE and TRUE instead of 0 and 1, in order to avoid a warning from package igraph * Bug fix: function OSOAs_hadamard did not work for n=8 * Bug fix: handling of s in SOAs2plus_regular had a bug (leading to failure for s=9, because 9 was treated as a prime). Now, SOAs2plus_regular, SOA2plus_regulart and createAB (file utilitiesCreate.R) all have the same requirements for s: primes up to 19, powers of 2 up to 32, powers of 3 up to 27 (presumably, the larger numbers do not really work well, but are in principle possible) Version 1.0-1, 16 December 2021 * expanded description in DESCRIPTION file, and added a reference * changed argument F to Fhat in internal function optimize * made a few changes to the documentation, as requested by CRAN * corrected a miswrite in a reference for createAB Version 1.0, 11 December 2021 * first version submitted to CRAN