Changelog

Source: NEWS.md

ecan 0.2.2.9000 (development)

• Added twinspan(), a native R implementation of TWINSPAN (Hill 1979) and modified TWINSPAN (Roleček et al. 2009). It is written in plain R from the published description of the algorithm, and is not a port of the original FORTRAN program. The known differences from the original are listed in ?twinspan, which also points to the twinspan package of Oksanen for those who need the results of the original program.
  • polish = "hill" (the default) follows the steps of Hill’s program, and reproduces it exactly on the dune, sipoo, varespec, mite, BCI and pyrifos data of ‘vegan’: the same groups of stands and of species, with the same numbers, divisions and eigenvalues, and on twenty randomly generated data sets. polish = "ecan" keeps the earlier way, written from the published description alone.
  • Rare pseudospecies are downweighted in the ordination as the original does, which can be turned off with downweight = FALSE.
  • Helpers: pseudospecies(), tw_ra(), tw_downweight(), tw_inertia(), tw_preference(), tw_hill_const() and tw_two_way().
  • stats::as.hclust() converts the result so that cls_color(), cls_add_group() and ggdendro::ggdendrogram() can be used.

ecan 0.2.2

CRAN release: 2026-08-22

• 2026-08-18

• Bug fix in ordination()

  • o_method = "pcoa" returned eigen values in $st_scores and nothing in $eig_val. It now returns the stand coordinates in $st_scores and the eigen values in $eig_val.

• $distance_method is NULL for “ca” and “dca”, which do not use a distance, as it already was for “pca”.

• Added tests for cluster(), df2table(), table2df(), dist2df(), ind_val() and the one-to-multi helpers.

• Bug fixes

  • shdi() gave NaN for h when an abundance was zero. A zero is now read as an absent species, as s already did.
  • ind_val() did not order its result at all. The species of a group are now given in decreasing order of ind.val.
  • cls_add_group() turned every label into NA when a single stand was missing from df. Only the labels of the missing stands are NA now: pad2longest() no longer lets an NA decide the width.
  • dist2df() dropped a distance of zero between two different plots. It now drops the diagonal only.
  • ordination() raised an unrelated error for an unknown o_method. It now names the method and lists the valid ones.

• ord_add_group() keeps the column named by group, even when that column is not one-to-multi to indiv.

• cols_one2multi() and select_one2multi() spell their argument include_self. The misspelt inculde_self is still accepted.

• twinspan(polish = "hill") takes the downweighting limits from tw_hill_const() instead of the defaults of tw_downweight(). The values are the same, so the results do not change.

ecan 0.2.1

CRAN release: 2023-07-07

• 2023-07-07

• Removed method “fsap” in ordination(), because package dave was archived.

ecan 0.2.0

CRAN release: 2023-03-23

• 2023-03-16

• Bug fix

• Release to CRAN

ecan 0.1.0

• 2022-05-24

• First release

  • Panels: Read data, Diversity, ISA (ind val), Cluster, Ordination.
  • Can download data.
  • Can show groups.