Base R 图图例中不同颜色的点和线

在本文中，我们将看到如何在基本 R 编程语言中绘制不同颜色的点和线。

创建用于演示的数据集：

R

A <- matrix( c( c(0,1,2,3,5), c(1,3,4,2,4)), ncol=2 )
B <- matrix( c( c(3,1,2,3,4), c(4,2,1,1,2)), ncol=2 )
C <- matrix( c( c(1,1,2,4,5), c(4,4,0,1,2)), ncol=2 )
data <- data.frame(A,B)
data

输出：

让我们看看上面的代码，其中 'A','B','C' 是矩阵的名称，在 c() 中输入向量由值组成。它还包含行数，即，'ncol' 为二。

用不同颜色在图形上绘制线和点

创建矩阵后，现在我们将绘制线和点。

Syntax: plot(x, y, type = “l”, lty = 1) 

              lines(x, y, type = “l”, lty = 1)

Parameters:

• x, y: coordinate vectors of points to join
• type: character indicating the type of plotting. Allowed value is : “p” for points
• lty: line types. Line types can either be specified as an integer (0=blank, 1=solid (default), 2=dashed, 3=dotted, 4=dotdash, 5=longdash, 6=twodash) or as one of the character strings “blank”, “solid”, “dashed”, “dotted”, “dotdash”, “longdash”, or “twodash”, where “blank” uses ‘invisible lines’ (i.e., does not draw them). 

电阻

# Plotting the lines and points
# here type b means we are plotting
# both points and line
plot( 0, type = "b", xlim = c(0,5),
     ylim = c(0,5) )
 
# defining the line column and colour
lines( A, col = "red" )
 
# defining the point column and colour
# here pch means the type of symbol
# we can choose from 1 to 25
points( A, col = "yellow", pch = 16 )
lines( C, col = "green" )
points( C, col = "pink", pch = 15 )
lines( B, col = "blue" )
points( B, col = "violet", pch = 17 )

输出：

在上图中，我们绘制了线条和点。没有指定哪一行代表什么，为了做到这一点，我们将使用图例函数为它们提供相同的标签。

添加图例

向绘图添加图例时，有一种主要方法可以修改图例位置。您可以将参数 x 设置为“top”、“topleft”、“topright”、“bottom”、“bottomleft”、“bottomright”、“left”、“right”或“center”，在这种情况下，您不需要必须设置参数 y。

在下面的代码中，在绘制图形后，我们现在添加一个 pch=c(NA, NA) 的图例，这意味着图例部分没有显示“pch”，表示点符号，我们可以根据需要从 1 到 25用户的选择。

电阻

A <- matrix( c( c(0,1,2,3,5), c(1,3,4,2,4)), ncol=2 )
B <- matrix( c( c(3,1,2,3,4), c(4,2,1,1,2)), ncol=2 )
C <- matrix( c( c(1,1,2,4,5), c(4,4,0,1,2)), ncol=2 )
data <- data.frame(A,B)
 
plot( 0, type = "b", xlim = c(0,5),
     ylim = c(0,5) )
lines( A, col = "red" )
points( A, col = "yellow",
       pch = 16 )
lines( C, col = "green" )
points( C, col = "pink", pch = 15 )
lines( B, col = "blue" )
points( B, col = "violet", pch = 17 )
 
legend( x = "topright",
        legend = c("Red line, Yellow points","Blue line,
                  iolet points","Green line,Pink points"),
        col = c("red","blue","green"), lwd=1, lty=c(1,1,1),
        pch=c(NA,NA), cex = 0.5 )

输出：

通过重叠向图例添加点符号

现在我们将只重叠图例，符号，正如我们之前观察到的，线，是可见的线图例而不是点符号。

所以我们要做的是，将值分配给“pch”，我们可以根据用户选择从 1 到 25 不等，每个数字代表一个点形状，即 pch =1，这是一个空心圆，pch = 19（实心圆）、pch = 21（实心圆）等。

电阻

# data
A <- matrix( c( c(0,1,2,3,5), c(1,3,4,2,4)), ncol=2 )
B <- matrix( c( c(3,1,2,3,4), c(4,2,1,1,2)), ncol=2 )
C <- matrix( c( c(1,1,2,4,5), c(4,4,0,1,2)), ncol=2 )
data <- data.frame(A,B)
 
# plot
plot( 0, type = "b", xlim=c(0,5), ylim=c(0,5) )
lines( A, col = "red" )
points( A, col = "yellow", pch=16 )
lines( C, col = "green" )
points( C, col = "pink", pch=15 )
lines( B, col = "blue" )
points( B, col = "violet", pch=17 )
 
# legend
legend( x="topright",
        legend=c("Red line, Yellow points","Blue line,
                iolet points","Green line,Pink points"),
        col=c("red","blue","green"), lwd=1, lty=c(1,1,1),
        pch=c(NA,NA),cex=0.5 )
 
legend( x="topright",
        legend=c("Red line, Yellow points","Blue line,
                violet points","Green line,Pink points"),
        col=c("yellow","purple","pink"), lwd=1, lty=c(0,0,0),
        pch=c(16,15,17),cex=0.5 )

输出

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