矩陣中的顏色數字根據它們的值

Question

我有一個2乘2的矩陣，我想根據它們的值爲數字着色（比如我有0-20的數字，我想要着色0-2 =藍色; 2-4 =天藍色...... 12-14 =黃色，18-20 =紅色等）。在Excel中，我只能使用Conditional Formatting選項使用3種顏色（請參見圖）。任何人都知道我是否可以在另一個程序中使用更多顏色（最好是R）。謝謝！ PS：請注意，我並不需要散熱圖或等高線圖，因爲我對數字的確切值感興趣。

Answer 1

這裏是一個解決方案，我希望它有助於

# 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])) 
    } 
}