2014-04-01 140 views
1

我想用一個柱的「x」與值1〜10我可以這樣做通過添加控制的手動指定的顏色的透明度「阿爾法= X」,但在這種情況下我看到暗顏色質點在我的散點圖中。任何人都可以幫忙嗎?控制顏色透明度GGPLOT2

這裏是我的代碼:

plot1 <- qplot(data=srna[srna$norm_sum > 0 & srna$len > 18 & srna$len < 25, ], x=position,y=norm_sum,colour= len) 
plot1 + geom_point(size=4) + 
    theme_bw()+ 
# scale_alpha_continuous(range = c(0.1, 0.8))+ 
    scale_colour_manual(values = c("19" = "pink","20" = "blue","21" = "green", "22" = "yellow","23" = "violet", "24" = "red"))+ 
    theme(panel.grid.minor.x = element_line(colour='grey94'),panel.grid.minor.y = element_line(colour='grey94'), 
     panel.grid.major.x = element_line(colour='lightgrey'),panel.grid.major.y = element_line(colour='lightgrey')) 
+1

能否請你加你的數據看起來像一個指示?頭(srna)'是適合的。 「暗色點」是什麼意思?另外,你可以描述*爲什麼*你想手動指定alpha?最後,你有沒有看着[scale_alpha_manual(http://docs.ggplot2.org/current/scale_manual.html)? – naught101

回答

0

試圖從the ggplot2 manual重現使用默認的數據你的問題(下面的代碼),我得到這個結果。也許你可以指出問題在這裏?

geom_point, control color transparency in ggplot2

# install.packages("ggplot2", dependencies = TRUE) 
library(ggplot2) 
p <- ggplot(mtcars, aes(wt, mpg)) 
p + geom_point(size=4, alpha = 0.5, aes(colour = factor(cyl))) + 
     theme_bw() + 
    scale_colour_manual(values = c("4" = "pink","6" = "blue", "8" = "green")) + 
    theme(panel.grid.minor.x = element_line(colour='grey94'), 
      panel.grid.minor.y = element_line(colour='grey94'), 
      panel.grid.major.x = element_line(colour='lightgrey'), 
      panel.grid.major.y = element_line(colour='lightgrey'))