R 在更改條形顏色時重新排序數據。 我如何防止這種情況？

Question

所以，我有一個數據集，我想把它畫成條形。 但是，一旦我添加顏色，R 就會重新排序我的數據集！

library("ggplot2")

data <- read.csv(file = "data.csv",
                 stringsAsFactors = TRUE)

# This is what I want position-wise
plot <- ggplot(data, aes(y=median,x=backend)) +
  geom_bar(stat = "identity", aes(fill=generic), position = position_dodge2(padding = .2), alpha = 0.75) +
  labs(title="Median", y="", x="Backends",fill="Generic")
print(plot)

# This is what I want color-wise
anydsl.plot <- ggplot(data, aes(y=median,x=backend)) +
  geom_bar(stat = "identity", aes(fill=ifelse(generic, "Yes", "No")), position = position_dodge2(padding = .2), alpha = 0.75) +
  labs(title="Median", y="", x="Backends", fill="Generic")
print(plot)

數據集如下：

backend,median,minimum,maximum,generic,threads
cpu,8.70,8.40,14.06,1,1
cpu,8.10,7.65,13.23,0,1
cpu,5.77,5.54,10.04,1,2
cpu,5.42,4.24,9.34,0,2
cpu,4.44,4.12,7.07,1,3
cpu,4.26,3.79,6.82,0,3
cpu,3.70,3.52,6.42,1,4
cpu,3.77,3.48,6.04,0,4
cpu,3.49,3.20,5.40,1,5
cpu,3.53,3.08,5.45,0,5
cpu,3.42,3.08,5.23,1,6
cpu,3.51,3.20,4.79,0,6
cpu,3.46,3.17,4.84,1,7
cpu,3.48,2.98,4.75,0,7
cpu,3.46,3.14,4.76,1,8
cpu,3.47,3.12,4.60,0,8
avx,4.49,4.47,8.85,1,1
avx,4.33,4.31,8.53,0,1
avx,3.58,3.27,6.10,1,2
avx,3.49,3.25,5.99,0,2
avx,3.38,2.97,5.36,1,3
avx,3.40,3.01,5.31,0,3
avx,3.43,2.98,4.62,1,4
avx,3.38,2.84,4.72,0,4
avx,3.40,2.93,4.60,1,5
avx,3.42,2.95,4.53,0,5
avx,3.43,2.97,4.49,1,6
avx,3.42,2.80,4.47,0,6
avx,3.46,3.06,4.49,1,7
avx,3.45,2.91,4.50,0,7
avx,3.46,2.98,5.18,1,8
avx,3.47,2.98,4.42,0,8
cuda,3.04,2.98,3.10,1,1
cuda,0.33,0.32,0.34,0,1
nvvm,3.40,3.33,3.46,1,1
nvvm,2.72,2.68,2.77,0,1
opencl,3.04,3.00,3.09,1,1
opencl,0.33,0.32,0.34,0,1

沒有我的自定義顏色的輸出是：

我的自定義顏色的輸出是：

如何獲得第一個圖但使用第二個圖的顏色？

Answer 1

問題是，通過在fill上映射ifelse(generic, "Yes", "No")你隱式地改變了分組變量。 獲得與group aes 上的第一個繪圖backend相同的分組

library(ggplot2)
library(dplyr)

data <- read.table(text = "backend,median,minimum,maximum,generic,threads
cpu,8.70,8.40,14.06,1,1
cpu,8.10,7.65,13.23,0,1
cpu,5.77,5.54,10.04,1,2
cpu,5.42,4.24,9.34,0,2
cpu,4.44,4.12,7.07,1,3
cpu,4.26,3.79,6.82,0,3
cpu,3.70,3.52,6.42,1,4
cpu,3.77,3.48,6.04,0,4
cpu,3.49,3.20,5.40,1,5
cpu,3.53,3.08,5.45,0,5
cpu,3.42,3.08,5.23,1,6
cpu,3.51,3.20,4.79,0,6
cpu,3.46,3.17,4.84,1,7
cpu,3.48,2.98,4.75,0,7
cpu,3.46,3.14,4.76,1,8
cpu,3.47,3.12,4.60,0,8
avx,4.49,4.47,8.85,1,1
avx,4.33,4.31,8.53,0,1
avx,3.58,3.27,6.10,1,2
avx,3.49,3.25,5.99,0,2
avx,3.38,2.97,5.36,1,3
avx,3.40,3.01,5.31,0,3
avx,3.43,2.98,4.62,1,4
avx,3.38,2.84,4.72,0,4
avx,3.40,2.93,4.60,1,5
avx,3.42,2.95,4.53,0,5
avx,3.43,2.97,4.49,1,6
avx,3.42,2.80,4.47,0,6
avx,3.46,3.06,4.49,1,7
avx,3.45,2.91,4.50,0,7
avx,3.46,2.98,5.18,1,8
avx,3.47,2.98,4.42,0,8
cuda,3.04,2.98,3.10,1,1
cuda,0.33,0.32,0.34,0,1
nvvm,3.40,3.33,3.46,1,1
nvvm,2.72,2.68,2.77,0,1
opencl,3.04,3.00,3.09,1,1
opencl,0.33,0.32,0.34,0,1", sep = ",", header = TRUE)

# This is what I want color-wise
anydsl.plot <- ggplot(data, aes(y=median,x=backend, group = backend)) +
  geom_bar(stat = "identity", aes(fill = ifelse(generic, "Yes", "No")), position = position_dodge2(padding = .2), alpha = 0.75) +
  labs(title="Median", y="", x="Backends", fill="Generic")
print(anydsl.plot)