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R language provides a large number of libraries to implement plotting functions. A pie chart, also known as a pie graph, is a circular statistical chart divided into several sectors, used to describe the relative relationship between quantities, frequencies, or percentages. R language uses the pie() function to create pie charts. The syntax is as follows: pie(x, labels = names(x), edges = 200, radius = 0.8, clockwise = FALSE, init.angle = if(clockwise) 90 else 0, density = NULL, angle = 45, col = NULL, border = NULL, lty = NULL, main = NULL, …) * x: A numeric vector representing the area of each sector. * labels: A character vector representing the labels for each sector area. * edges: This parameter has little use, it refers to the number of edges of the polygon (the circle's outline is similar to a polygon with many edges). * radius: The radius of the pie chart. * main: The title of the pie chart. * clockwise: A logical value indicating whether the pie chart slices are divided in clockwise direction. * angle: Sets the angle of the shading. * density: The density of the shading. The default value is NULL. * col: Represents the color of each sector, equivalent to a palette. To draw a pie chart, you need to prepare: a vector reflecting the quantity, labels for each part, and colors for each part (optional). Next, we will draw a simple pie chart: ## Example # Data preparation info = c(1, 2, 4, 8) # Naming names = c("Google", "Tutorial", "Taobao", "Weibo") # Coloring (optional) cols = c("#ED1C24","#22B14C","#FFC90E","#3f48CC") # Plotting pie(info, labels=names, col=cols) When executing the plotting program, a PDF file (Rplots.pdf) will be generated in the current directory. Opening the file, you can see the graphics effect as follows: !(#) We can also use png(), jpeg(), bmp() functions to set the output file format to images: ## Example # Data preparation info =c(1, 2, 4, 8) # Naming names=c("Google", "Tutorial", "Taobao", "Weibo") # Coloring (optional) cols =c("#ED1C24","#22B14C","#FFC90E","#3f48CC") # Set output image png(file='tutorial-pie.png', height=300, width=300) # Plotting pie(info, labels=names, col=cols) Next, we will set a title for the pie chart. For Chinese fonts, you need to set the font parameter family='GB1', or you can set your own font library. For details, refer to: (#). ## Example # Data preparation info = c(1, 2, 4, 8) # Naming names = c("Google", "Tutorial", "Taobao", "Weibo") # Coloring (optional) cols = c("#ED1C24","#22B14C","#FFC90E","#3f48CC") # Calculate percentage piepercent = paste(round(100*info/sum(info)), "%") # Plotting pie(info, labels=piepercent, main = "Website Analysis", col=cols, family='GB1') # Add color sample legend legend("topright", names, cex=0.8, fill=cols) !(#) To draw a 3D pie chart, you can use the pie3D() function from the plotrix library. Before using it, we need to install it first: install.packages("plotrix", repos = "https://mirrors.ustc.edu.cn/CRAN/") ## Example # Load plotrix library(plotrix) # Data preparation info =c(1, 2, 4, 8) # Naming names=c("Google", "Tutorial", "Taobao", "Weibo") # Coloring (optional) cols =c("#ED1C24","#22B14C","#FFC90E","#3f48CC") # Set file name, output as png png(file="3d_pie_chart.png") # Draw 3D chart, family should be set to the Chinese font library supported by your system pie3D(info,labels=names,explode =0.1, main ="3D Map",family="STHeitiTC-Light") The generated image is as follows: !(#)