矩阵中的颜色数字根据它们的值

Question

我有一个2乘2的矩阵，我想根据它们的值为数字着色（比如我有0-20的数字，我想要着色0-2 =蓝色; 2-4 =天蓝色...... 12-14 =黄色，18-20 =红色等）。在Excel中，我只能使用Conditional Formatting选项使用3种颜色（请参见图）。任何人都知道我是否可以在另一个程序中使用更多颜色（最好是R）。谢谢！ PS：请注意，我并不需要散热图或等高线图，因为我对数字的确切值感兴趣。

Answer 1

这里是一个解决方案，我希望它有助于

# you need this for the colour ramp 
library(RColorBrewer) 

# setup 
rows <- 10 
collumns <- 10 

# data matrix 
zVals <- round(rnorm(rows*collumns), 2) 
z <- matrix(zVals, rows, collumns) 

# pick the number of colours (granularity of colour scale) 
nColors <- 100 

# create the colour pallete 
cols <-colorRampPalette(colors=c("blue", "grey", "red"))(nColors) 

# get a zScale for the colours 
zScale <- seq(min(z), max(z), length.out = nColors) 

# function that returns the nearest colour given a value of z 
findNearestColour <- function(x) { 
     colorIndex <- which(abs(zScale - x) == min(abs(zScale - x))) 
     return(cols[colorIndex]) 
} 

# empty plot 
plot(1, 1, type = "n", xlim = c(1, rows), ylim = c(1, collumns), 
    axes = F, xlab = "", ylab = "") 

# populate it with the data 
for(r in 1:rows){ 
    for(c in 1:collumns){ 
     text(c, r, z[c,r], col = findNearestColour(z[c,r])) 
    } 
}