在图（R）中围绕一个圆圈包装/弯曲文本

您也可以尝试arctext使用以下plotrix软件包：

library(plotrix)

# set up a plot with a circle
plot(x = 0, y = 0, xlim = c(-2, 2), ylim = c(-2, 2))
draw.circle(x = 0, y = 0, radius = 1)

# add text
arctext(x = "wrap some text", center = c(0, 0), radius = 1.1, middle = pi/2)
arctext(x = "counterclockwise", center = c(0, 0), radius = 1.1, middle = 5*pi/4,
        clockwise = FALSE, cex = 1.5)
arctext(x = "smaller & stretched", center = c(0, 0), radius = 1.1, middle = 2*pi ,
        cex = 0.8, stretch = 1.2)

要获得更多的自定义机会（轻描淡写；请参阅漂亮的小插曲），您可以查看一下circlize软件包。通过设置facing = "bending"为circos.text，文本环绕一个圆圈。

library(circlize)

# create some angles, labels and their corresponding factors
# which determine the sectors 
deg <- seq(from = 0, to = 300, by = 60)
lab <- paste("some text", deg, "-", deg + 60)   
factors <- factor(lab, levels = lab)

# initialize plot
circos.par(gap.degree = 10)
circos.initialize(factors = factors, xlim = c(0, 1))
circos.trackPlotRegion(ylim = c(0, 1))

# add text to each sector  
lapply(factors, function(deg){
  circos.updatePlotRegion(sector.index = deg, bg.col = "red")
circos.text(x = 0.5, y = 0.5, labels = as.character(deg), facing = "bending")
})
circos.clear()

更新：
在circlize0.2.1版本，circos.text有两个新选项：bending.inside其等同于原始bending和bending.outside（参照图11晕影）。因此，使用以下命令很容易在图的下半部分中显示文本bending.outside：

circos.par(gap.degree = 10)
circos.initialize(factors = factors, xlim = c(0, 1))
circos.trackPlotRegion(ylim = c(0, 1))

lapply(factors[1:3], function(deg){
  circos.updatePlotRegion(sector.index = deg, bg.col = "red")
  circos.text(x = 0.5, y = 0.5, labels = as.character(deg), facing = "bending.outside")
})

lapply(factors[4:6], function(deg){
  circos.updatePlotRegion(sector.index = deg, bg.col = "red")
  circos.text(x = 0.5, y = 0.5, labels = as.character(deg), facing = "bending.inside")
})
circos.clear()