将Alpha值添加到点阵xyplot面板函数 [英] Add alpha value to lattice xyplot panel function

问题描述

我想在 xyplot 面板函数中分配两个alpha值:带有 alpha = 0.3 的 points 和带有 alpha = 1 的 lines .这是一个示例:

 库(晶格)库(sp)数据(鼠标)xyplot(elev〜Copper，data = meuse，groups = factor(soil)，grid = TRUE，scales = list(tck = c(1,0)，x = list(cex = 1.1)，y = list(cex = 1.1)))，auto.key = list(空格='right'，text = c("1"，"2"，"3")))，参数设置= list(superpose.symbol = list(pch = 20，cex = 1，col = c(#006837"，#41ab5d"，#fd8d3c")))，类型= c("p"，平滑")，col.line = c(#006837"，#41ab5d"，#fd8d3c")，lwd = 5，panel = function(x，...){panel.xyplot(x，...，alpha = 0.3)panel.lines(x，...，alpha = 1)}) 

解决方案

十六进制值可以读取为#rrggbbaa" ，其中r =红色，g =绿色，b =蓝色和a =α.由于不透明度的十进制值为0到255，因此采用传统的rgb表示法；30％不透明度的值应为 round((256/100)* 30)= 77 ，而十六进制值为 4d (有一些示例列表

I want to assign two alpha values in xyplot panel function: points with alpha= 0.3 and lines with alpha=1. Here is an example:

library(lattice)
library(sp)
data(meuse)

xyplot(elev~ copper,data=meuse,groups=factor(soil),grid = TRUE,scales=list(tck=c(1,0), x=list(cex=1.1), y=list(cex=1.1)),
       auto.key = list(space = 'right',text=c("1", "2", "3")),
       par.settings = list(superpose.symbol = list(pch =20, cex = 1,
                                                   col = c("#006837", "#41ab5d","#fd8d3c"))),
      type = c("p", "smooth"),col.line =c("#006837", "#41ab5d","#fd8d3c"),lwd = 5,
      panel = function(x, ...) {
                panel.xyplot(x, ..., alpha = 0.3)
                panel.lines(x, ...,  alpha = 1)
            })

解决方案

An hex value can be read as "#rrggbbaa" where r = red, g = green, b = blue and a = alpha. Since the decimal values for opacity range from 0 to 255, in a traditional rgb notation; the value for 30% opacity would be round((256/100)*30) = 77, and hexadecimal value for this is 4d (there is a list with some examples here for reference and a conversion table dec - hex can be found here).

Therefore, you just need to add 4d at the end of your hex code for the points color as:

col = c("#0068374d", "#41ab5d4d","#fd8d3c4d")

and remove

panel = function(x, ...) {
            panel.xyplot(x, ..., alpha = 0.3)
            panel.lines(x, ...,  alpha = 1)
        }

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