旋转chordDiagram中的标签(R circlize)

chooseCRANmirror(graphics=FALSE, ind=1)
knitr::opts_chunk$set(echo = TRUE)

这是来自circlize包的一些代码,用于创建和弦图.现在标签与圆的边缘平行.是否可以将标签旋转90度,使其垂直于圆圈？

install.packages('circlize')

## 
## The downloaded binary packages are in
##  /var/folders/w0/lbylgmhd5sz6nt0rps_bcq5h0000gn/T//RtmpXzl54m/downloaded_packages

library(circlize)

## ========================================
## circlize version 0.4.5
## CRAN page: https://cran.r-project.org/package=circlize
## Github page: https://github.com/jokergoo/circlize
## Documentation: http://jokergoo.github.io/circlize_book/book/
## 
## If you use it in published research, please cite:
## Gu, Z. circlize implements and enhances circular visualization 
##   in R. Bioinformatics 2014.
## ========================================

set.seed(999)
mat = matrix(sample(18, 18), 3, 6)
rownames(mat) = paste0("Start", 1:3)
colnames(mat) = paste0("End", 1:6)
chordDiagram(mat)

根据您的示例数据,这是一种方法：

grid.col <- setNames(rainbow(length(unlist(dimnames(mat)))), union(rownames(mat), colnames(mat)))
par(mar = c(0, 0, 0, 0), mfrow = c(1, 2))

# original image
chordDiagram(mat, grid.col = grid.col) 

# now, the image with rotated labels
chordDiagram(mat, annotationTrack = "grid", preAllocateTracks = 1, grid.col = grid.col)
circos.trackPlotRegion(track.index = 1, panel.fun = function(x, y) {
  xlim = get.cell.meta.data("xlim")
  ylim = get.cell.meta.data("ylim")
  sector.name = get.cell.meta.data("sector.index")
  circos.text(mean(xlim), ylim[1] + .1, sector.name, facing = "clockwise", niceFacing = TRUE, adj = c(0, 0.5))
  circos.axis(h = "top", labels.cex = 0.5, major.tick.percentage = 0.2, sector.index = sector.name, track.index = 2)
}, bg.border = NA)

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