| b_analyse {pctax} | R Documentation | 
Beta_diversity Ordination: dimensionality reduction
Description
Species abundance data can be preprocessed with Hellinger transformation or chord transformation data before PCA analysis. Because the Hellinger distance or chord distance with-without data is equal to \sqrt2\sqrt{1-Ochiai\ similarity}, therefore, the sorting diagram (type 1 scale) of PCA analysis after Hellinger transformation or chord transformation with-without data is internal sample The distance between the squares is the Ochiai distance. \sqrt2\sqrt{1-Ochiai\ similarity} is a distance measure, which is also suitable for the analysis of species data. The processed data is then used for pca without norm.
Usage
b_analyse(otutab, ...)
## S3 method for class 'data.frame'
b_analyse(
  otutab,
  norm = TRUE,
  method = c("pca", "nmds"),
  group = NULL,
  dist = "bray",
  ndim = 2,
  scale = FALSE,
  ...
)
Arguments
| otutab | an otutab data.frame, samples are columns, taxs are rows. | 
| ... | add | 
| norm | should normalized or not? (hellinger) | 
| method | one of "pca","pcoa","ca","dca","nmds","plsda","tsne","umap","lda","all" | 
| group | if needed, give a group vector | 
| dist | if use pcoa or nmds, your can choose a dist method (default: bray) or input a distance matrix. | 
| ndim | how many dimension be kept? (default:2). 3 for b_res_3d() | 
| scale | scale, default: FALSE | 
Value
b_res object
References
https://www.jianshu.com/p/9694c0b6302d https://zhuanlan.zhihu.com/p/25501130
Examples
data(otutab, package = "pcutils")
b_analyse(otutab, method = "pca") -> b_res
plot(b_res, "Group", metadata)