geom_line 的条件颜色

Question

我想要一条线通过给定的点，并为指定间隔内的值指定颜色。但是我只能得到指定颜色的多行而不是会在其子间隔上改变颜色的单行。

可重现的例子如下：

require(ggplot2)
require(plotly)

vectX <- c(-5,-4.5,-3.2,-2.1,-0.8,0.1,1.3,2.7,3.6,4.4,5)
vectY <- c(-2.3,1.4,2.7,0.3,-0.4,1.5,3.9,2.4,0.5,-1.2,1.4)

requestedQuantilesZscores <-  c(0.0,0.25,0.5,0.75,1.0)
zScores <- base::scale(vectY, center = TRUE, scale = TRUE)
quantilesZscore <- stats::quantile(zScores, requestedQuantilesZscores, na.rm = TRUE)

theDataFrame <- base::data.frame(theX = vectX, theY = vectY, theZ = zScores)

valuesColor <- c('green','red','blue','yellow','orange')
theDataFrame$conditionalColor <- ifelse(theDataFrame$theZ > quantilesZscore[[4]], valuesColor[[1]] ,
      ifelse(theDataFrame$theZ > quantilesZscore[[3]] & theDataFrame$theZ <= quantilesZscore[[4]], valuesColor[[2]],
        ifelse(theDataFrame$theZ > quantilesZscore[[2]] & theDataFrame$theZ <= quantilesZscore[[3]], valuesColor[[3]],
          ifelse(theDataFrame$theZ <= quantilesZscore[[2]], valuesColor[[4]], valuesColor[[5]]))))

theGGplotLine <- ggplot(theDataFrame) +
  geom_line(aes(x = theX, y = theY, color = conditionalColor)) +
  xlab('X') + ylab('Y') +
  scale_colour_manual(values = valuesColor) +
  theme(legend.position='none')

theGGplotLine

(plotly::ggplotly(theGGplotLine))

Answer 1

如果我理解正确你想要什么，你只需要在你的 ggplot 代码中添加一个不同的分组

theGGplotLine <- ggplot(theDataFrame) +
  geom_line(aes(x = theX, y = theY, color = conditionalColor, group = 1)) +
  xlab('X') + ylab('Y') +
  scale_colour_manual(values = valuesColor) +
  theme(legend.position='none')

这给出了所有点连接的一条线，但颜色取决于 conditionalColor 列。如有必要，这样的分组也可以基于单独的列

Answer 2

答案结合了 user2738526 为原始问题提供的解决方案的要素，以及

的解决方案

它使用 geom_segment，并使每个段 link 达到下一个 (x, y) 值，而不考虑颜色。

代码变为

require(ggplot2)
require(plotly)
require((dplyr))

vectX <- c(-5,-4.5,-3.2,-2.1,-0.8,0.1,1.3,2.7,3.6,4.4,5)
vectY <- c(-2.3,1.4,2.7,0.3,-0.4,1.5,3.9,2.4,0.5,-1.2,1.4)

requestedQuantilesZscores <-  c(0.0,0.25,0.5,0.75,1.0)
zScores <- base::scale(vectY, center = TRUE, scale = TRUE)
quantilesZscore <- stats::quantile(zScores, requestedQuantilesZscores, na.rm = TRUE)

theDataFrame <- base::data.frame(theX = vectX, theY = vectY, theZ = zScores)

theDataFrame <- theDataFrame %>%
  arrange(theX) %>%
  mutate(theNextX = lead(theX), theNextY = lead(theY))

valuesColor <- c('green','red','blue','magenta','orange')
theDataFrame$conditionalColor <- ifelse(theDataFrame$theZ > quantilesZscore[[4]], valuesColor[[1]] ,
        ifelse(theDataFrame$theZ > quantilesZscore[[3]] & theDataFrame$theZ <= quantilesZscore[[4]], valuesColor[[2]],
               ifelse(theDataFrame$theZ > quantilesZscore[[2]] & theDataFrame$theZ <= quantilesZscore[[3]], valuesColor[[3]],
                      ifelse(theDataFrame$theZ <= quantilesZscore[[2]], valuesColor[[4]], valuesColor[[5]]))))

theGGplotLine <- ggplot(theDataFrame, aes(x = theX, y = theY)) +
  geom_segment(aes(xend = theNextX, yend = theNextY, color = conditionalColor)) +
  xlab('X') + ylab('Y') +
  scale_colour_manual(values = valuesColor) +
  theme_bw() +
  theme(legend.position='none')

theGGplotLine

(plotly::ggplotly(theGGplotLine))

geom_line 的条件颜色

Conditional color for geom_line

r

ggplot2

plotly

ggplotly