将 x 轴刻度更改为立方根，而不使用 trans_new() 转换原始数据

Question

我需要将 ggplot 图的 x 轴更改为立方根比例，而不转换原始数据。我下面的代码一直有效，但是随着新的 R 更新，我收到错误，

if (zero_range(as.numeric(transformation$transform(limits)))) { 中的错误： 需要 TRUE/FALSE 时缺少值

我想知道是否有人知道为什么现在会发生此错误和/或解决方案/解决方法来在立方根刻度上绘制我的图形。谢谢！

前几行数据：

structure(list(site = c("US", "US", "US", "US", "US", "US"), 
    Transect = c(1L, 1L, 1L, 1L, 1L, 1L), Plot = c(100L, 103L, 
    106L, 109L, 112L, 115L), Year = c(2020L, 2020L, 2020L, 2020L, 
    2020L, 2020L), SYear = c("2020-2021", "2020-2021", "2020-2021", 
    "2020-2021", "2020-2021", "2020-2021"), E.Delta = c(-0.0380000000000109, 
    -0.0930000000000746, -0.0950000000000273, -0.0709999999999127, 
    -0.104000000000042, -0.0989999999999327), I = c(1, 1, 1, 
    1, 1, 1), AllRtedPctCov = c(0, 0, 0, 0, 0, 0), NoRtedVeg = c(1, 
    1, 1, 1, 1, 1), PerCov.15 = structure(c(1L, 1L, 1L, 1L, 1L, 
    1L), levels = c("0", "1"), class = "factor")), row.names = c(NA, 
6L), class = "data.frame")

**我的代码：**

transform_cuberoot = function(){
  trans_new('cuberoot',
            transform = function(x) x^(1/3),
            inverse = function(x) x^3,
            breaks = c(0, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0),
            domain = c(-Inf, Inf))
} 

 
ggplot(df, aes(x = I, y = E.Delta, color = PerCov.15)) +
  geom_point(size = 1.5) +
  facet_wrap(~site + SYear, scales = "free") +
  theme_classic() +
  geom_hline(yintercept = 0, linetype = "dashed", color = "red") +
  labs(x = "Inundation-Duration", y = "Change in Elevation", color =" Percent Rooted Cover") +
  scale_colour_brewer(labels= c("<15%", ">15%"), type = "qual", palette = 3) + # qual 3 or seq 1
  theme(axis.title.x = element_text(size = 16, vjust = -2),
        axis.title.y = element_text(size = 16, vjust = 5),
        legend.title = element_text(size = 16),
        legend.text = element_text(size = 16),
        strip.background = element_blank(),
        strip.text = element_text(size = 18),
        axis.text = element_text(size = 14),
        plot.margin = unit(c(2,2,2,2), "cm"),
        panel.spacing = unit(3, "lines"))+
  scale_x_continuous(trans = transform_cuberoot(), breaks = c(0, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0),labels=c(0, 0.01, 0.1, " ", 0.3, " ", " ", 0.6, " ", " ", " ", 1.0)) 

我也尝试过使用解决方法，

coord_trans(x = transform_cuberoot())

而不是

trans = transform_cuberoot()

中的

scale_x_continuous

参数。这可以工作，但会删除其他重要的绘图功能，例如 y = 0 处的虚线和 y 轴线。它还会产生 18 条警告：

在transform(..., self = self)中： 变换在 x 轴上引入了无限值

请参阅下面的示例，了解我正在寻找的图形与我通过解决方法能够生成的图形。

我想要/尝试重新创建（在 0 处水平线并为每个站点包裹）：

我目前的解决方法：

Answer 1

您可以通过将立方根变换的域限制为非负值来解决此问题，即使用

domain=c(0, Inf)

。

注意：正如 @BenBolker 已经指出的那样，使用示例数据无法重现该问题，因此我将其更改为包含零值。经过一些实验后，仅当映射到

x

的变量包含一些小的、接近零的值时，才会出现问题。由此我可以猜测这与比例的（默认）扩展有关，即使用

expand = c(0, 0)

也可以正常工作。

library(ggplot2)
library(scales)

df$I <- c(0.0, 0.01, 0.1, 0.8, 0.9, 1.0)
transform_cuberoot <- function() {
  trans_new("cuberoot",
    transform = function(x) x^(1 / 3),
    inverse = function(x) x^3,
    domain = c(0, Inf)
  )
}

ggplot(df, aes(x = I, y = E.Delta, color = PerCov.15)) +
  geom_point(size = 1.5) +
  facet_wrap(~ site + SYear, scales = "free") +
  theme_classic() +
  geom_hline(yintercept = 0, linetype = "dashed", color = "red") +
  labs(
    x = "Inundation-Duration", y = "Change in Elevation",
    color = " Percent Rooted Cover"
  ) +
  scale_colour_brewer(
    labels = c("<15%", ">15%"),
    type = "qual", palette = 3
  ) + # qual 3 or seq 1
  scale_x_continuous(
    transform = transform_cuberoot(),
    breaks = c(0, 0.01, 0.1, 0.3, 0.6, 1.0)
  )

仅供参考，这里我使用

domain = c(-Inf, Inf)

重现该问题：

transform_cuberoot <- function() {
  trans_new("cuberoot",
    transform = function(x) x^(1 / 3),
    inverse = function(x) x^3,
    domain = c(-Inf, Inf)
  )
}

ggplot(df, aes(x = I, y = E.Delta, color = PerCov.15)) +
  geom_point(size = 1.5) +
  facet_wrap(~ site + SYear, scales = "free") +
  theme_classic() +
  geom_hline(yintercept = 0, linetype = "dashed", color = "red") +
  labs(
    x = "Inundation-Duration", y = "Change in Elevation",
    color = " Percent Rooted Cover"
  ) +
  scale_colour_brewer(
    labels = c("<15%", ">15%"),
    type = "qual", palette = 3
  ) + # qual 3 or seq 1
  scale_x_continuous(
    transform = transform_cuberoot(),
    breaks = c(0, 0.01, 0.1, 0.3, 0.6, 1.0)
  )
#> Error in if (zero_range(as.numeric(transformation$transform(limits)))) {: missing value where TRUE/FALSE needed