如何停止颜色回收

Question

我试图使用filled.contour在r中创建一个热图，我有一个看起来有点像下面那个的数据框，但颜色被回收，这对它来说非常无用。我做错了什么？

x <- c(seq(15, 75, by = 5))
y <- rep(c(100,200,300,400,500, 600, 700, 800),each=length(x))
z <- sample(0:34, length(y), replace=TRUE)
z <- z/10000

d <- data.frame(x, y, z)


resolution <- 0.1

a <- interp(x=d$x, y=d$y, z=d$z, 
        xo=seq(min(d$x),max(d$x),by=resolution), 
        yo=seq(min(d$y),max(d$y),by=resolution),
        duplicate="mean")

MyHeatMapColours <-colorRampPalette(c("red","yellow","springgreen","royalblue"))(50)

filled.contour(a, col = MyHeatMapColours, nlevels = 49)

Answer 1

我猜测interp来自包：akima。你的例子并不是最小的，因为它需要很长的时间来运行，所以我在不失一般性的情况下减少了resiolution。我认为使用＆＃34; level＆＃34;更安全。而不是＆＃34; nlevels＆＃34;，虽然我不能告诉你为什么会这样：

library(akima)   # which does have an `interp`-function
x <- c(seq(15, 75, by = 5))
y <- rep(c(100,200,300,400,500, 600, 700, 800),each=length(x))
z <- sample(0:34, length(y), replace=TRUE)
z <- z/10000

d <- data.frame(x, y, z)
resolution <- 0.5

a <- interp(x=d$x, y=d$y, z=d$z, 
        xo=seq(min(d$x),max(d$x),by=resolution), 
        yo=seq(min(d$y),max(d$y),by=resolution),
        duplicate="mean")

MyHeatMapColours <-colorRampPalette(c("red","yellow","springgreen","royalblue"))(49) 
#colors are supposed to be one less than length of levels.

filled.contour(a, col = MyHeatMapColours, 
               levels = seq(min(z),max(z), length=50))