R语言低级绘图函数-axis

时间:2021-08-21 16:57:05

axis函数用来在一张图表上添加轴线,区别于传统的x轴和y轴,axis 允许在上,下,左, 右4个方向添加轴线

以x轴为例,一条轴线包含3个元素,水平的一条横线,叫做axis line , 刻度线, 叫做tick line, 对应的标签 labels

基本用法:

通过side 参数设置需要添加的轴线的方向,从下边开始,沿逆时针方向,数字为1到4

代码示例:

par(oma = c(1, 1, 1, 1), mfrow = c(1, 4))
plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
text(x = 3, y = 3, labels = "side = 1", cex = 2)
box()
axis(side = 1)
plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
text(x = 3, y = 3, labels = "side = 2", cex = 2)
box()
axis(side = 2)
plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
text(x = 3, y = 3, labels = "side = 3", cex = 2)
box()
axis(side = 3)
plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
text(x = 3, y = 3, labels = "side = 4", cex = 2)
box()
axis(side = 4)

效果图如下:

R语言低级绘图函数-axis

参数设置:

at : 需要添加刻度的数值,默认会根据变量的取值范围计算几个合适的刻度,也可以手工指定

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, at = c(0, 2, 4, 6))

效果图如下:

R语言低级绘图函数-axis

lables : 指定在刻度上需要标记的内容,默认就是刻度对应的值

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, at = c(0, 2, 4, 6), labels = paste(c(0, 2, 4, 6), "A", sep = ""))

效果图如下:

R语言低级绘图函数-axis

tick : 逻辑值,是否显示轴线,包括刻度线和对应的轴线, FALSE 表示不显示

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
axis(side = 1, tick = F)

效果图:

R语言低级绘图函数-axis

line : 轴线的位置

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, line = 1)

效果图如下:

R语言低级绘图函数-axis

lwd : 设置 axis  line 和 tick line  的宽度

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, line = 1, lwd = 2)

效果图如下:

R语言低级绘图函数-axis

lwd.tick : 设置tick line的宽度

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, line = 1, lwd = 1, lwd.tick = 2)

效果图如下:

R语言低级绘图函数-axis

lty : 设置axis line 和tick line的线条类型

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, line = 1, lty = 3)

效果图如下:

R语言低级绘图函数-axis

col  : 设置axis line 和 tick.line 的线条颜色

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, line = 1, col = "blue")

效果图如下:

R语言低级绘图函数-axis

col.ticks  : 设置tick line的颜色

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, line = 1, col = "blue", col.ticks = "red")

效果图如下:

R语言低级绘图函数-axis

pos : 对轴线的位置进行调整,当pos 设置了对应的值之后会覆盖line 参数的值

代码示例:

plot(1:5, 1:5, xlim = c(0,6), ylim = c (0,6), type = "n", axes = F)
box()
axis(side = 1, pos = 1)

效果图如下:

R语言低级绘图函数-axis