使用scale_fill_manual手动分配颜色仅适用于某些六边形尺寸

Question

我正在尝试创建一个散点图，它由六位数的计数器总结。我希望用户能够为色标定义计数中断。我使用scale_fill_manual()进行此操作。但奇怪的是，它有时只能起作用。在下面的MWE中，使用给定的种子值，如果xbins=10，则会出现如下问题：

但是，例如，如果xbins=20或40，情节似乎没有问题：

我的MWE如下：

library(ggplot2)
library(hexbin)
library(RColorBrewer)

set.seed(1)
xbins <- 20

x <- abs(rnorm(10000))
y <- abs(rnorm(10000))
minVal <- min(x, y)
maxVal <- max(x, y)
maxRange <- c(minVal, maxVal)
buffer <- (maxRange[2] - maxRange[1]) / (xbins / 2)
h <- hexbin(x = x, y = y, xbins = xbins, shape = 1, IDs = TRUE,
            xbnds = maxRange, ybnds = maxRange)
hexdf <- data.frame (hcell2xy(h),  hexID = h@cell, counts = h@count)
my_breaks <- c(2, 4, 6, 8, 20, 1000)
clrs <- brewer.pal(length(my_breaks) + 3, "Blues")
clrs <- clrs[3:length(clrs)]
hexdf$countColor <- cut(hexdf$counts, breaks = c(0, my_breaks, Inf), 
                        labels = rev(clrs))

ggplot(hexdf, aes(x = x, y = y, hexID = hexID, fill = countColor)) +
  scale_fill_manual(values = levels(hexdf$countColor)) +
  geom_hex(stat = "identity") + 
  geom_abline(intercept = 0, color = "red", size = 0.25) + 
  coord_fixed(xlim = c(-0.5, (maxRange[2] + buffer)), 
              ylim = c(-0.5, (maxRange[2] + buffer))) + 
  theme(aspect.ratio=1)

我的目标是调整此代码，以便绘图没有问题（突然某些六边形的大小和形状与其余六边形不同），无论分配给xbins的值如何。但是，我很疑惑可能导致某些xbins值出现此问题。任何建议都将不胜感激。

编辑：

在考虑@bdemarest和@Axeman的评论后，我正在更新示例代码。我按照@Axeman建议的链接中最流行的答案，并且相信当你在整数向量上使用scale_fill_continuous()时它更有用。在这里，我正在研究因子向量scale_fill_manual()。结果，我仍然无法实现这一目标。谢谢。

library(ggplot2)
library(hexbin)
library(RColorBrewer)

set.seed(1)
xbins <- 10

x <- abs(rnorm(10000))
y <- abs(rnorm(10000))
minVal <- min(x, y)
maxVal <- max(x, y)
maxRange <- c(minVal, maxVal)
buffer <- (maxRange[2] - maxRange[1]) / (xbins / 2)
bindata = data.frame(x=x,y=y,factor=as.factor(1))

h <- hexbin(bindata, xbins = xbins, IDs = TRUE, xbnds = maxRange, ybnds = maxRange)

counts <- hexTapply (h, bindata$factor, table)
counts <- t (simplify2array (counts))
counts <- melt (counts)
colnames (counts)  <- c ("factor", "ID", "counts")
counts$factor =as.factor(counts$factor)

hexdf <- data.frame (hcell2xy (h),  ID = h@cell)
hexdf <- merge (counts, hexdf)

my_breaks <- c(2, 4, 6, 8, 20, 1000)
clrs <- brewer.pal(length(my_breaks) + 3, "Blues")
clrs <- clrs[3:length(clrs)]
hexdf$countColor <- cut(hexdf$counts, breaks = c(0, my_breaks, Inf), labels = rev(clrs))

ggplot(hexdf, aes(x = x, y = y, fill = countColor)) +
  scale_fill_manual(values = levels(hexdf$countColor)) +
  geom_hex(stat = "identity") + 
  geom_abline(intercept = 0, color = "red", size = 0.25) + 
  coord_cartesian(xlim = c(-0.5, maxRange[2]+buffer), ylim = c(-0.5, maxRange[2]+ buffer)) + theme(aspect.ratio=1)

Answer 1

您可以在'geom'中定义颜色，而不是'scale'来修改绘图的比例：

ggplot(hexdf, aes(x = x, y = y)) + 
geom_hex(stat = "identity",fill =hexdf$countColor)