在 R 编程中将颜色转换为其 rgb 值 – col2rgb()函数

R 语言中的col2rgb()函数用于将 R 颜色转换为 RGB（红/绿/蓝）。

Syntax: col2rgb(col)

Parameters:
col: vector of any of the three kinds of R color specifications, i.e, either a color name (listed by colors()), a hexadecimal string of the form “#rrggbb” or “#rrggbbaa”, or a positive integer i meaning palette()[i]

示例 1：

# R program to illustrate
# col2rgb function
  
# Calling the col2rgb() function
col2rgb("# 08a0ff")
col2rgb("peachpuff")
col2rgb(1:8)
col2rgb(paste0("gold", 1:4))

输出：

[, 1]
red      8
green  160
blue   255
      [, 1]
red    255
green  218
blue   185
      [, 1] [, 2] [, 3] [, 4] [, 5] [, 6] [, 7] [, 8]
red      0  255    0    0    0  255  255  190
green    0    0  205    0  255    0  255  190
blue     0    0    0  255  255  255    0  190
      [, 1] [, 2] [, 3] [, 4]
red    255  238  205  139
green  215  201  173  117
blue     0    0    0    0

示例 2：

# R program to illustrate
# col2rgb function
  
# Calling the col2rgb() function
col2rgb(c(blu = "royalblue", reddish = "tomato"))
col2rgb(c(red = "red", hex = "# abcdef"))
col2rgb(c(palette = 1:3))

输出：

blu reddish
red    65     255
green 105      99
blue  225      71
      red hex
red   255 171
green   0 205
blue    0 239
      palette1 palette2 palette3
red          0      255        0
green        0        0      205
blue         0        0        0