How to use column with colours to change the colour of points using ggplot2 in R?

R ProgrammingServer Side ProgrammingProgramming

If we have a colour column in an R data frame and we want to change the point colours in ggplot2 using that column then colour argument will be used. For example, if we have a data frame called df that contains three columns say x, y, and color then the scatterplot between x and y with the colour of points using color column can be created by using the command ggplot(df,aes(x,y))+geom_point(colour=df$color)

Example

Consider the below data frame −

Live Demo

> x<-rnorm(20)
> y<-rnorm(20)
> col<-sample(c("blue","red","green"),20,replace=T)
> df<-data.frame(x,y,col)
> df

Output

             x          y   col
1   1.92321342  1.2183501 green
2   0.73342537 -0.6477975 green
3  -1.00606105 -1.2697246   red
4   0.73504980 -0.5593899   red
5  -0.39976314  0.1185340 green
6  -1.15940677 -0.7219141 green
7   1.81313147 -2.1268507  blue
8  -0.47278398 -1.0414317  blue
9  -1.33914777 -0.2756125  blue
10  0.05742411  1.4000877  blue
11 -0.13134085 -0.8916141 green
12  0.87743445 -0.4291995 green
13  0.55897765  0.2815842  blue
14  0.51374603 -1.0219416  blue
15  0.27037163  0.7545370  blue
16  0.02100292  0.2674216 green
17  0.73620835  0.6262369  blue
18 -0.11391829 -0.7456059 green
19 -0.64697468  0.6713425   red
20  0.37972640  3.7717047   red

Loading ggplot2 package and creating scatterplot between x and y −

> library(ggplot2)
> ggplot(df,aes(x,y))+geom_point()

Output

Creating the scatterplot between x and y with colour of points in col column −

> ggplot(df,aes(x,y))+geom_point(colour=df$col)

Output

raja
Published on 05-Mar-2021 07:17:06
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