NEWS.md
When permuting plots, balance is now only required within blocks. Requested by @dbaranger in #27
numPerms() gains argument check that works analogously to the same argument of allPerms() to request or suppress checking of the permutation design when computing the number of permutations. Users should not normally need to touch this default of TRUE.
check() gains argument num_perms to request or suppress the computing of the number of possible permutations for the current design. The default is TRUE, meaning the number of permutations is computed.
numPerms() tries harder to avoid floating point issues when computing the number of permutations for the current design. #41shuffleFree() allowed shuffleFree(x = 1:10), with x passed immediately to sample.int(), which is incorrect and raises an error in the development version of R (at the time of writing). Reported by Brian Ripley.allPerms() was calling allSeries() with the incorrect number of permutations, leading to problems with shuffleSet() also. #28 reported by Cajo ter Braak
The example in ?check was made to suppress package startup messages from vegan.
This release was purely to avoid issues with CRAN as a new release of vegan had been released and the example reference material hadn’t been updated to match.
shuffleSet() wasn’t returning a matrix if nset = 1 and allPerms was invoked because of a low set of possible permutations. GitHub Issue #19
This is small update to permute, focused mainly on ensuring the many combinations of restrictions on permutations allowed by the package work. An extensive test suite has been written which covers ~87% of the package’s codebase at the time of release.
Permutation matrices produced by shuffleSet() are now printed in a more compact form.
Better heuristics in check() allow for more reliable permutations (i.e. fewer duplicate permutations) when the set is small. This has increased the minperms setting. Consequently we generate all possible permutations up to ~500,000 more often as we now randomly sample from the entirely generated set rather than randomly generate permutations. This provides a small performance hit in some rare cases.
shuffleSet() has a new argument quietly = FALSE which is passed on to check().
A number of bugs were fixed. See the Changelog and the Bug reports on github for details.
how(), a new function to create permutation designs. This replaces the deprecated function permControl.
permute gains the addition of true blocking structures with which to restrict the permutations. Blocks sit as the outermost layer of the permutations, and can contain plots which in turn contain samples. In contrasts to plots, blocks are never permuted and samples are never shuffled between blocks. Permutation only ever happens within blocks.
To facilitate this, plot-level strata are now specified via Plots() instead of via the old strata argument of how(). Blocks are specified via a new argument blocks, which takes a factor variable.
A new suite of extractor and replacement functions is provided with which to interact with permutation designs created by how(). Extractor functions have namesgetFoo(), whereFoo()is a component of the design. Replacement functions have namessetFoo`. The replacement function are especially for use by package authors wishing to alter permutation within their functions. The extractor functions are recommended for all users wishing to extract features of the permutation design.
As a convenience for users, the function will now work with objects of classes "how", "Plots" or "Within" to allow quick updating of features of the permutation design. This approach is intended for interactive use at the top-level and not within functions, where the new setFoo replacement functions should be used.
shuffleSet() is enhanced in this version. Firstly, the function now returns a classed object which has a print() method to allow for compact printing of the design elements used to generate the set of permutations. Second, shuffleSet() will sample nset permutations from the entire set of permutations should a small number of possible permutations trigger generation of the entire set. This avoids the generation of a set of non-unique permutations. Finally the random seed that generated the set is stored as an attribute.
allPerms() no longer assumes that samples are in block and/or plot ordering.
The package vignette is much expanded in this version with new sections on using permute within functions that will be of interest to package authors wishing to use permute in their packages.
permControl() is deprecated in favour of how().
permuplot() is broken and effectively defunct given the changes to the way permutation are defined and the addition of blocks. permuplot() is no longer exported from the package namespace.