CajoterBraak/douconca: v1.1.6

R library `douconca` analyzes multi-trait multi-environment ecological data by double constrained correspondence analysis (ter Braak et al. 2018) using `vegan` and native R code. It has a `formula` interface for the trait- (column-) and environment- (row-) models, which allows to assess, for example, the importance of trait interactions in shaping ecological communities. Throughout the two step algorithm of ter Braak et al. (2018) is used. This algorithm combines and extends community- (sample-) and species-level analyses, i.e. the usual community weighted means (CWM)-based regression analysis and the species-level analysis of species-niche centroids (SNC)-based regression analysis. The CWM regressions are specified with an environmental formula and the SNC regressions are specified with a trait formula. dcCA finds the environmental and trait gradients that optimize these regressions.