R06-R语言作图

画图的目的是为了展示数据

常用可视化R包和函数

作图的三类

1.基础包-绘图函数

实例

plot(iris ,1 ,iris,3,col = iris,5) text(6.5,4, labels = 'hello')

2.ggplot2

library(ggplot2)

ggplot(data = iris)+

geom_point(mapping = aes(x = Sepal.Length, y = Petal.Length,color = Species))

2.1 入门级绘图模板

ggplot(data = <DATA>)+<GEOM_FUNCTION>(mapping = aes(<MAPPINGS>)

ggplot(data = iris)+geom_point(mapping = aes(x = Sepal.Length, y = Petal.Length))

ggplot2的特殊语法:列名不带引号,行末写加号

2.2属性设置（颜色、大小、透明度、点的形状、线型等）

2.2.1 手动设置

ggplot(data = iris) +

geom_point(mapping = aes(x = Sepal.Length, y = Petal.Length),

size = 5, # 点的大小5mm

alpha = 0.5, # 透明度 50%

shape = 8) # 点的形状

2.2.2映射：按照数据框的某一列来定义图的某个属性

ggplot(data = iris)+

geom_point(mapping = aes(

x = Sepal.Length,

y = Petal.Length,

color = Species))

映射:根据数据的某一列的内容分配颜色

手动设置:把图形设置为一个或n个颜色，与数据内容无关

Q:能否自行指定映射的具体颜色

ggplot(data = iris)+

geom_point(mapping = aes(

x = Sepal.Length,

y = Petal.Length,

color = Species))+

scale_color_manual(values = c("blue","grey","red"))

ggplot(data = iris)+

geom_point(mapping = aes(

x = Sepal.Length,

y = Petal.Length,

color = Species))+

scale_color_brewer(palette = "Set1")

Q2:区分color和fill两个属性

Q2-1 空心形状和实心形状都用color设置颜色

ggplot(data = iris)+

geom_point(mapping = aes(

x = Sepal.Length,

y = Petal.Length,

color = Species),

shape = 17) #17号，实心的例子

ggplot(data = iris)+

geom_point(mapping = aes(

x = Sepal.Length,

y = Petal.Length,

color = Species),

shape = 2) #2号，空心的例子

Q2-2 既有边框又有内心的，才需要color和fill两个参数

ggplot(data = iris)+

geom_point(mapping = aes(

x = Sepal.Length,

y = Petal.Length,

color = Species),

shape = 24,

color="red",

fill = "yellow") #24号，双色的例子

2.3几何对象

几何对象可以叠加

方法一

ggplot(data = iris) +

geom_smooth(mapping = aes(x = Sepal.Length, y = Petal.Length))+

geom_point(mapping = aes(x = Sepal.Length, y = Petal.Length))

方法二

ggplot(data = iris,mapping = aes(x = Sepal.Length, y = Petal.Length))+

geom_smooth()+

geom_point()#简版写法

ggplot2.4位置

ggplot(data = iris,mapping = aes(x = Species,

y = Sepal.Width,

fill = Species)) +

geom_boxplot()+

geom_point()

作图后，点与点发生重叠

ggplot(data = iris,mapping = aes(x = Species,

y = Sepal.Width,

fill = Species)) +

geom_boxplot()+

geom_jitter()

#geom_point(position = "jitter")

geom_jitter()后坐标系中的点散开

ggplot2.5坐标系

ggplot(data = iris,mapping = aes(x = Species,

y = Sepal.Width,

fill = Species)) +

geom_boxplot()+

geom_jitter()+

coord_flip()

横纵坐标互换翻转

theme_bw()

去掉灰色格子

ggplot语法总结

图层的叠放顺序先写现放

3.ggpubr #新手友好型 ggplot2简化和美化 褒贬不一

library(ggpubr)

ggscatter(iris,x="Sepal.Length", y="Petal.Length",color="Species")

ggpubr

library(ggpubr)

p = ggboxplot(iris, x = "Species", y = "Sepal.Length",

color = "Species", shape = "Species",add = "jitter")

p

ggpubr可以实现组间比较

>my_comparisons <- list( c("setosa", "versicolor"),

c("setosa", "virginica"),

c("versicolor", "virginica") )

>p + stat_compare_means(comparisons = my_comparisons,

aes(label = after_stat(p.signif)))

4.save_export.R

图片保存

ggplot2系列

ggsave("iris_box_ggpubr.png")

ggsave(p,filename="iris_box_ggpubr2.png")

通用：三段论

保存的函数及文件名 pdf("test.pdf")

作图代码 ...........

画完了，关闭画板 dev.off( )

ggsave系列保存

p <- ggboxplot(iris, x = "Species",

y = "Sepal.Length",

color = "Species",

shape = "Species",

add = "jitter")

ggsave(p,filename = "iris_box_ggpubr.png")

eoffice包 导出为ppt,全部元素都是可编辑模式

library(eoffice)

topptx(p,"iris_box_ggpubr.pptx")

画图的正确思维