In this section, we'll produce a color differentiated scatter plot with respect to a third variable. Let's begin by implementing the following steps:

1. Choose a subset of dataset 1 (gapminder) and select a few countries. Use the following subset command:

dfs <- subset(df,Country %in%c("Germany","India","China","United States"))

2. Make a scatter plot of the two variables and change the x and y titles:

p1<- ggplot(df,aes_string(x=var1,y=var2))+)geom_point(color=2,shape=2)+xlim(0,10000)+xlab(name1)+ylab(name2)

3. Then, change the colors and shapes of the points for plot 1:

p2 <- ggplot(df,aes_string(x=var1,y=var2))+geom_t(aes(color=Country,shape=Country))+xlim(0,10000)+xlab(name1)+ylab(name2)

4. Now, group points by Country, mapped by color and shape, for plot 3 and plot 4:

grid.arrange(p1, p2, nrow = 2) 

The following plots should be obtained on completion of this example: