ggplot2的默认分面功能功能不够强大，支持的自定义参数也比较少，今天介绍的这个包可以对分面进行超多改头换面的操作！
- 安装
- 使用
- facet_wrap2()/facet_grid2()
- facet_nest()
- facet_manual()
- 分面的条带设置
安装
代码语言：javascript复制install.packages("ggh4x")
# install.packages("devtools")
devtools::install_github("teunbrand/ggh4x")
使用
首先我们建立一个默认的分面图形。
代码语言：javascript复制library(ggplot2)
p <- ggplot(mpg, aes(displ, hwy, colour = as.factor(cyl))) geom_point()
labs(x = "Engine displacement", y = "Highway miles per gallon")
guides(colour = "none")
p facet_wrap(~ class)
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默认的分面是上面这样的，而今天要介绍的ggh4x提供了更加强大的函数gacet_wrap2()。
facet_wrap2()/facet_grid2()
默认情况下和facet_wrap()函数完全相同：
library(ggh4x)
p facet_wrap2(vars(class))
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支持为每一个分面图增加坐标刻度，并支持移除或保留x轴或者y轴的标签：
代码语言：javascript复制p facet_wrap2(vars(class), axes = "all", remove_labels = "x")
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支持更加强大的分面图形布局，还可以进行留白：
代码语言：javascript复制p facet_wrap2(vars(class), nrow = 4, ncol = 4, trim_blank = F)
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facet_wrap()是针对一个变量进行分面的，facet_grid()是针对两个变量进行分面的，所以ggh4x也提供了facet_grid2()函数扩展其功能！
p facet_grid2(vars(year), vars(drv), axes = "all", remove_labels = "y")
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默认的facet_grid()函数中的scales参数，只能控制整体的x轴或者y轴，但是facet_grid2()函数提供了额外的independent参数，可以让所有分面的坐标都自行调节（不明白的可以用默认的facet_grid画图比较下）。
p facet_grid2(vars(year), vars(drv), scales = "free_x", independent = "x")
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facet_nest()
嵌套分面，可以实现以下效果，非常实用。
代码语言：javascript复制new_iris <- transform(
iris,
Nester = ifelse(Species == "setosa", "Short Leaves", "Long Leaves")
)
iris_plot <- ggplot(new_iris, aes(Sepal.Width, Sepal.Length))
geom_point()
iris_plot
facet_nested(~ Nester Species) # 分面在一起，嵌套
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还可以对嵌套分面进行各种细节调整：
代码语言：javascript复制iris_plot
facet_nested(~ Nester Species, nest_line = element_line(linetype = 2)) # 线型
theme(strip.background = element_blank(),
ggh4x.facet.nestline = element_line(colour = "blue")) # 颜色
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可以把分面标签放在下面：
代码语言：javascript复制iris_plot
geom_point(data = ~ transform(.x, Species = NULL, Nester = "All")) # 添加一个包含所有点的分面
facet_nested(~ Nester Species, switch = "x") # 放在下面
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还提供了facet_nested_wrap()函数，作为facet_wrap()的变体：
p
facet_nested_wrap(
vars(cyl, drv), dir = "v", strip.position = "left",
axes = "all", remove_labels = "x"
)
theme(strip.placement = "outside")
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facet_manual()
为分面图形提供更加强大的布局，支持自定义各种复杂的自定义布局。
代码语言：javascript复制design <- matrix(c(1,2,3,2), 2, 2)
p facet_manual(vars(factor(drv)), design = design)
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也支持使用类似patchwork::plot_layout()风格的布局参数：使用连续的字母代替图形，不同的行数代表行，#代表占位符：
design <- "
A##
AB#
#BC
##C
"
p facet_manual(vars(drv), design = design)
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使用heights/widths参数控制布局中每行和每列的高度和宽度：
p facet_manual(
vars(drv), design = design,
heights = 4:1, # 4行，每行的高度依次是4,3,2,1
widths = unit(1:3, "cm") # 3列，每列的宽度依次是1,2,3
)
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只要给出合适的布局，重叠也是可以的：
代码语言：javascript复制design <- "
AA#
ACB
#BB
"
p facet_manual(vars(drv), design = design)
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分面的条带设置
提供了strip_vanilla()/strip_themed()/strip_nested()函数用以控制strip的诸多细节。
p2 <- p
theme(strip.background = element_rect(colour = "black", size = 2),
axis.line.y = element_line(colour = "black", size = 2))
p2
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代码语言：javascript复制p2 facet_wrap2(vars(year), strip = strip_vanilla(clip = "on"))
ggtitle('clip = "on"')
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代码语言：javascript复制p2 facet_wrap2(vars(year), strip = strip_vanilla(clip = "off"))
ggtitle('clip = "off"')
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代码语言：javascript复制df <- data.frame(
long = paste("A long title that is going to make then",
"smaller title take up too much space"),
short = LETTERS[1:3],
x = 1:3, y = 1:3
)
p2 <- ggplot(df, aes(x, y))
geom_point()
theme(strip.text.y.left = element_text(angle = 0),
strip.placement = "outside",
plot.title.position = "plot")
p2
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代码语言：javascript复制p2 facet_grid2(long short ~ ., switch = "y",
strip = strip_vanilla(size = "constant"))
ggtitle('size = "constant"')
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代码语言：javascript复制p2 facet_grid2(long short ~ ., switch = "y",
strip = strip_vanilla(size = "variable"))
ggtitle('size = "variable"')
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代码语言：javascript复制ridiculous_strips <- strip_themed(
# Horizontal strips
background_x = elem_list_rect(fill = c("limegreen", "dodgerblue")),
text_x = elem_list_text(colour = c("dodgerblue", "limegreen"),
face = c("bold", "bold")),
by_layer_x = TRUE,
# Vertical strips
background_y = elem_list_rect(
fill = c("gold", "tomato", "deepskyblue")
),
text_y = elem_list_text(angle = c(0, 90)),
by_layer_y = FALSE
)
p facet_grid2(class ~ drv year, strip = ridiculous_strips)
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代码语言：javascript复制p facet_grid2(
. ~ drv year,
strip = strip_themed(
background_x = list(NULL, element_rect(colour = "black"), element_blank(),
element_rect(fill = "black")),
text_x = list(NULL, NULL, NULL, element_text(colour = "white"))
)
)
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代码语言：javascript复制p facet_wrap2(
vars(cyl, drv), ncol = 4,
strip = strip_nested(bleed = FALSE)
)
ggtitle('bleed = FALSE')
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代码语言：javascript复制p facet_grid2(
cols = vars("Outer label", "Inner label"),
switch = "x", strip = strip_vanilla()
)
ggtitle("strip_vanilla()")
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代码语言：javascript复制p facet_grid2(
cols = vars("Outer label", "Inner label"),
switch = "x", strip = strip_nested()
)
ggtitle("strip_nested()")
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以上就是今天的内容，希望对你有帮助哦！
