我使用了以下ggplot命令:
ggplot(survey, aes(x = age)) + stat_bin(aes(n = nrow(h3), y = ..count.. / n), binwidth = 10)
+ scale_y_continuous(formatter = "percent", breaks = c(0, 0.1, 0.2))
+ facet_grid(hospital ~ .)
+ theme(panel.background = theme_blank())
生产
然而，我想将facet标签更改为更短的内容(如Hosp 1, Hosp 2…)，因为它们现在太长了，看起来很局促(增加图形的高度不是一个选项，它将占用文档中的太多空间)。我查看了facet_grid帮助页面，但不知道如何操作。
当前回答
在挣扎了一段时间后，我发现我们可以使用fct_relevel()和fct_recode()从forcats结合来改变facet的顺序以及修复facet标签。我不确定它是否被设计支持，但它确实有效!看看下面的图表:
library(tidyverse)
before <- mpg %>%
ggplot(aes(displ, hwy)) +
geom_point() +
facet_wrap(~class)
before
after <- mpg %>%
ggplot(aes(displ, hwy)) +
geom_point() +
facet_wrap(
vars(
# Change factor level name
fct_recode(class, "motorbike" = "2seater") %>%
# Change factor level order
fct_relevel("compact")
)
)
after
由reprex包于2020-02-16创建(v0.3.0)
其他回答
添加另一个类似于@domi的解决方案，解析数学符号、上标、下标、圆括号/方括号等。
library(tidyverse)
theme_set(theme_bw(base_size = 18))
### create separate name vectors
# run `demo(plotmath)` for more examples of mathematical annotation in R
am_names <- c(
`0` = "delta^{15}*N-NO[3]^-{}",
`1` = "sqrt(x,y)"
)
# use `scriptstyle` to reduce the size of the parentheses &
# `bgroup` to make adding `)` possible
cyl_names <- c(
`4` = 'scriptstyle(bgroup("", a, ")"))~T~-~5*"%"',
`6` = 'scriptstyle(bgroup("", b, ")"))~T~+~10~degree*C',
`8` = 'scriptstyle(bgroup("", c, ")"))~T~+~30*"%"'
)
ggplot(mtcars, aes(wt, mpg)) +
geom_jitter() +
facet_grid(am ~ cyl,
labeller = labeller(am = as_labeller(am_names, label_parsed),
cyl = as_labeller(cyl_names, label_parsed))
) +
geom_text(x = 4, y = 25, size = 4, nudge_y = 1,
parse = TRUE, check_overlap = TRUE,
label = as.character(expression(paste("Log"["10"], bgroup("(", frac("x", "y"), ")")))))
### OR create new variables then assign labels directly
# reverse facet orders just for fun
mtcars <- mtcars %>%
mutate(am2 = factor(am, labels = am_names),
cyl2 = factor(cyl, labels = rev(cyl_names), levels = rev(attr(cyl_names, "names")))
)
ggplot(mtcars, aes(wt, mpg)) +
geom_jitter() +
facet_grid(am2 ~ cyl2,
labeller = label_parsed) +
annotate("text", x = 4, y = 30, size = 5,
parse = TRUE,
label = as.character(expression(paste("speed [", m * s^{-1}, "]"))))
由reprex包于2019-03-30创建(v0.2.1.9000)
这个解决方案非常接近于@domi，但是它通过获取前4个字母和最后一个数字来缩短名称。
library(ggplot2)
# simulate some data
xy <- data.frame(hospital = rep(paste("Hospital #", 1:3, sep = ""), each = 30),
value = rnorm(90))
shortener <- function(string) {
abb <- substr(string, start = 1, stop = 4) # fetch only first 4 strings
num <- gsub("^.*(\\d{1})$", "\\1", string) # using regular expression, fetch last number
out <- paste(abb, num) # put everything together
out
}
ggplot(xy, aes(x = value)) +
theme_bw() +
geom_histogram() +
facet_grid(hospital ~ ., labeller = labeller(hospital = shortener))
下面是另一个解决方案，它遵循@naught101给出的解决方案的精神，但更简单，也没有在ggplot2的最新版本上抛出警告。
基本上，首先创建一个命名字符向量
hospital_names <- c(
`Hospital#1` = "Some Hospital",
`Hospital#2` = "Another Hospital",
`Hospital#3` = "Hospital Number 3",
`Hospital#4` = "The Other Hospital"
)
然后将它用作标签器，只需修改@naught101给出的最后一行代码
... + facet_grid(hospital ~ ., labeller = as_labeller(hospital_names))
更改底层因子级别的名称，如下所示:
# Using the Iris data
> i <- iris
> levels(i$Species)
[1] "setosa" "versicolor" "virginica"
> levels(i$Species) <- c("S", "Ve", "Vi")
> ggplot(i, aes(Petal.Length)) + stat_bin() + facet_grid(Species ~ .)
如果你有两个面医院和房间，但只想重命名其中一个，你可以使用:
facet_grid( hospital ~ room, labeller = labeller(hospital = as_labeller(hospital_names)))
使用基于矢量的方法重命名两个面(如naught101的答案)，你可以这样做:
facet_grid( hospital ~ room, labeller = labeller(hospital = as_labeller(hospital_names),
room = as_labeller(room_names)))
