Themes

参考：ggplot2: Elegant Graphics for Data Analysis (opens new window)

ggplot2的主题系统theme，主要用来美化图片，控制图片颜色、字体、边距、背景等。

主题系统由四个主要部分组成：

主题元素(element, e.g. plot.title, axis.ticks.x)
元素设置函数(element function, e.g. element_text())
theme()函数，是设置主题的接口。
完整的主题(e.g. theme_bw(), theme_grey())

# 1. 修改主题

修改主题的通用公式：

# 直接修改
plot + theme(element.name = element_function())

## 或者，在完整主题基础之上修改
plot + theme_bw() + theme(element.name = element_function())

1
2
3
4
5

# 2. 元素设置函数

ggplot2内置了4种基本的元素设置函数: 文本、线条、矩形和空白。每个元素设置函数都有一组用于控制外观的参数。

# 2.1. element_text

element_text() 绘制文本标签和标题。可以控制字体、颜色、大小、hjust、vjust、角度（以度为单位）和行高（作为字体大小的比例)等。

base <- ggplot(mpg, aes(cty, hwy, color = factor(cyl))) +
  geom_jitter() + 
  geom_abline(colour = "grey50", size = 2)

base_t <- base + labs(title = "This is a ggplot") + xlab(NULL) + ylab(NULL)
base_t + theme(plot.title = element_text(size = 16))
base_t + theme(plot.title = element_text(face = "bold", colour = "red"))
base_t + theme(plot.title = element_text(hjust = 1))

1
2
3
4
5
6
7
8

# 2.2. element_line

element_line() 控制线条颜色、粗细和线型等。

base + theme(panel.grid.major = element_line(colour = "black"))
base + theme(panel.grid.major = element_line(size = 2))
base + theme(panel.grid.major = element_line(linetype = "dotted"))

1
2
3

# 2.3. element_rect

element_rect() 绘制矩形，主要用于背景设置，控制填充颜色，边框颜色、大小和线型等。

base + theme(plot.background = element_rect(fill = "linen", colour = "skyblue", size = 2, linetype = "dashed"))

# 2.3. element_blank

element_blank(), 用于隐藏元素，且不分配空间。

base
last_plot() + theme(panel.grid.minor = element_blank())
last_plot() + theme(panel.grid.major = element_blank())

1
2
3

使用theme_update()可以起到与base plot 中 par()类似的效果，保存当前设置，在将来绘图中重用。

old_theme <- theme_update(
  plot.background = element_rect(fill = "lightblue3", colour = NA),
  panel.background = element_rect(fill = "lightblue", colour = NA),
  axis.text = element_text(colour = "linen"),
  axis.title = element_text(colour = "linen")
)
base
theme_set(old_theme)
base

1
2
3
4
5
6
7
8
9

# 3. 主题元素

ggplot2主题元素可以分为5类：plot, axis, legend, panel and facet.

# 3.1. plot元素

base + theme(plot.background = element_rect(colour = "grey50", size = 2))
base + theme(
  plot.background = element_rect(colour = "grey50", size = 2),
  plot.margin = margin(20, 20, 20, 20)
)
base + theme(plot.background = element_rect(fill = "lightblue"))

1
2
3
4
5
6
7

# 3.2. axis元素

df <- data.frame(x = 1:3, y = 1:3)
base <- ggplot(df, aes(x, y)) + geom_point()

# Accentuate the axes
base + theme(axis.line = element_line(colour = "grey50", size = 1))
# Style both x and y axis labels
base + theme(axis.text = element_text(color = "blue", size = 12))
# Useful for long labels
base + theme(axis.text.x = element_text(angle = -90, vjust = 0.5))

1
2
3
4
5
6
7
8
9

# 3.3. legend元素

df <- data.frame(x = 1:4, y = 1:4, z = rep(c("a", "b"), each = 2))
base <- ggplot(df, aes(x, y, colour = z)) + geom_point()

base + theme(
  legend.background = element_rect(
    fill = "lemonchiffon", 
    colour = "grey50", 
    size = 1
  )
)
base + theme(
  legend.key = element_rect(color = "grey50"),
  legend.key.width = unit(0.9, "cm"),
  legend.key.height = unit(0.75, "cm")
)
base + theme(
  legend.text = element_text(size = 15),
  legend.title = element_text(size = 15, face = "bold")
)

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

# 3.4. panel元素

base <- ggplot(df, aes(x, y)) + geom_point()
# Modify background
base + theme(panel.background = element_rect(fill = "lightblue"))

# Tweak major grid lines
base + theme(
  panel.grid.major = element_line(color = "gray60", size = 0.8)
)
# Just in one direction  
base + theme(
  panel.grid.major.x = element_line(color = "gray60", size = 0.8)
)

1
2
3
4
5
6
7
8
9
10
11
12

df <- data.frame(x = 1:4, y = 1:4, z = c("a", "a", "b", "b"))
base_f <- ggplot(df, aes(x, y)) + geom_point() + facet_wrap(~z)

base_f
base_f + theme(panel.spacing = unit(0.5, "in"))

base_f + theme(
  strip.background = element_rect(fill = "grey20", color = "grey80", size = 1),
  strip.text = element_text(colour = "white")
)

1
2
3
4
5
6
7
8
9
10
11

# 4. 完整主题

theme_grey: ggplot2默认主题
theme_bw: 与theme_grey类似，白色背景
theme_linedraw
theme_light
theme_dark
theme_minimal
theme_classic: 常用，类似base plot
theme_void: 空主题

# 5. theme_Publication

参考ggplot_theme_Publication (opens new window)

theme_Publication <- function(base_size=14, base_family="sans") {
      library(grid)
      library(ggthemes)
      (theme_foundation(base_size=base_size, base_family=base_family)
       + theme(plot.title = element_text(face = "bold",
                                         size = rel(1.2), hjust = 0.5),
               text = element_text(),
               panel.background = element_rect(colour = NA),
               plot.background = element_rect(colour = NA),
               panel.border = element_rect(colour = NA),
               axis.title = element_text(face = "bold",size = rel(1)),
               axis.title.y = element_text(angle=90,vjust =2),
               axis.title.x = element_text(vjust = -0.2),
               axis.text = element_text(), 
               axis.line.x = element_line(colour="black"),
               axis.line.y = element_line(colour="black"),
               axis.ticks = element_line(),
               panel.grid.major = element_line(colour="#f0f0f0"),
               panel.grid.minor = element_blank(),
               legend.key = element_rect(colour = NA),
               legend.position = "bottom",
               legend.direction = "horizontal",
               legend.key.size= unit(0.2, "cm"),
               legend.margin = unit(0, "cm"),
               legend.title = element_text(face="italic"),
               plot.margin=unit(c(10,5,5,5),"mm"),
               strip.background=element_rect(colour="#f0f0f0",fill="#f0f0f0"),
               strip.text = element_text(face="bold")
       ))
      
}

scale_fill_Publication <- function(...){
      library(scales)
      discrete_scale("fill","Publication",manual_pal(values = c("#386cb0","#fdb462","#7fc97f","#ef3b2c","#662506","#a6cee3","#fb9a99","#984ea3","#ffff33")), ...)
      
}

scale_colour_Publication <- function(...){
      library(scales)
      discrete_scale("colour","Publication",manual_pal(values = c("#386cb0","#fdb462","#7fc97f","#ef3b2c","#662506","#a6cee3","#fb9a99","#984ea3","#ffff33")), ...)
      
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43

使用方法：

source("https://cdn.jsdelivr.net/gh/koundy/ggplot_theme_Publication/R/ggplot_theme_Publication.R")
ggplot(mtcars, aes(wt, mpg, color = as.factor(cyl))) +
	geom_point(size = 3) + 
	theme_Publication()

1
2
3
4

编辑

#ggplot2 #theme

上次更新: 2021/07/12, 11:19:29

← Legends Facets→