#r grid

[graphicdesignblg]

R Grid by Nono Martínez Alonso Twitter: @Trendgrafeed

[sasrandme]

Graphics for Statistics - figures with ggplot - Chapter 3

chapter3

Table of Contents

1 Chapter 3

1.1 Figure 3.4 - simple bar chart

1.2 Figure 3.5 - simple bar chart

1.3 Figure 3.7

1 Chapter 3

Graphics out of the book Graphics for Statistics and Data Analysis with R by Kevin Keen (book home page)

here are the data

item<-c("Canada", "Mexico", "Saudi Arabia", "Venezuela", "Nigeria") amount<-c(2460,1538,1394,1273,1120) amount<-amount/1000 df <- data.frame(item=factor(1:5,labels=item),amount=amount) barrel <- read.jpeg("barrel.jpg")

1.1 Figure 3.4 - simple bar chart

we use geom_bar to create the bar chart

customizing the y-axis by using scale_y_continuous: limits set the limits, expand defines the multiplicative and additive expansion constants

coord_flip rotates it (so we get a horizontal bar chart)

than we set the background to white

set the colour of the axis lines to black (we have to do this to axis.line not just axis.line.x because of inheritance)

get rid of the vertical axis

set colour of the ticks of the x-axis to black

get rid of the ticks of the y-axis

set the colour of the axis labels to black

change the adjustment of the labels of vertical axis

get rid of the grid lines (they are still visible if one looks carefully)

ggplot(df,aes(y=amount,x=reorder(item,-as.numeric(item)))) + geom_bar(stat="identity",fill="white",colour="black") + scale_y_continuous("Millions of Barrels per Day",limits=c(0,2.5),expand=c(0,0)) + xlab("") + coord_flip() + theme(panel.background=element_rect(fill="white"), axis.line=element_line(colour="black"), axis.line.y=element_blank(), axis.ticks.x=element_line(colour="black"), axis.ticks.y=element_blank(), axis.text=element_text(colour="black",size=11), axis.text.y=element_text(hjust=0), panel.grid=element_blank()) ggsave("fig3_4.png")

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1.2 Figure 3.5 - simple bar chart

we use geom_point to create the chart with dots (set the size of the dots to 3)

via geom_segment we add the dotted lines (linetype=3)

customizing the x-axis by using scale_x_continuous: limits set the limits, expand defines the multiplicative and additive expansion constants

set the colour of the axis lines to black (we have to do this to axis.line not just axis.line.x because of inheritance)

get rid of the vertical axis

set colour of the ticks of the x-axis to black

get rid of the ticks of the y-axis

set the colour of the axis labels to black

than we set the background to transparent and the colour of the frame to black (panel.background=element_rect)

get rid of the grid lines (they are still visible if one looks carefully)

get rid of of the title of the y-axis

set the colour and the size of the title of the x-axis to black and 11 respectively

ggplot(df,aes(x=amount,y=item)) + geom_point(size=3) + geom_segment(aes(yend=as.numeric(item)),xend=0,linetype=3) + scale_x_continuous("Millions of Barrels per Day",limits=c(0,2.5),expand=c(0,0)) + theme(axis.line=element_line(colour="black"), axis.line.y=element_blank(), axis.ticks.y=element_blank(), axis.ticks.x=element_line(colour="black"), axis.text=element_text(colour="black",size=11), panel.background=element_rect(fill="transparent",colour="black"), panel.grid=element_blank(), axis.title.y=element_blank(), axis.title.x=element_text(colour="black",size=11) ) ggsave("fig3_5.png")

Saving 7 x 6.99 in image

1.3 Figure 3.7

the clipart can be downloaded here

we need the ReadImages package for reading this jpeg

we need the grid graphics package to divide the plot and insert to several parts

first we load two additional packages (ReadImages for reading the jpeg and grid for the grid graphics functions)

the next part (definition of the dot chart) is exactly the same as in figure 3.5

load the jpeg with the barrel (barrel <- read.jpeg("barrel.jpg"))

the next commands are part of the grid package, which is the underlying graphics system of ggplot2

grid.newpage moves to a new page

pushViewport adds a new viewport (plotting region) to the page (via x and y one can set the position), beginning in the top left corner, setting the width to 0.6 relative to the page and the height to 0.95; just sets the adjustment

print(p,newpage=F) prints the dot chart in this viewport

popViewport() closes the viewport

create another viewport next to the other one with width 0.4 and the same height

grid.raster inserts the picture of the barrel

grid.text inserts the text

library(grid) library(ReadImages) p <- ggplot(df,aes(x=amount,y=reorder(item,amount))) + geom_point(size=3) + geom_segment(aes(yend=reorder(item,amount)),xend=0,linetype=3) + scale_x_continuous("Millions of Barrels per Day",limits=c(0,2.5),expand=c(0,0)) + theme(axis.line=element_line(colour="black"), axis.line.y=element_blank(), axis.ticks.y=element_blank(), axis.text=element_text(colour="black",size=12), panel.background=element_rect(fill="white",colour="black"), panel.grid=element_blank(), axis.title.y=element_blank(), axis.title.x=element_text(colour="black",size=11) ) barrel <- read.jpeg("barrel.jpg") grid.newpage() pushViewport(viewport(x=unit(0,"line"),y=unit(1,"npc")-unit(2,"mm"),width=0.6,height=0.95,name="vp1",just=c("left","top"))) print(p,newpage=F) popViewport() pushViewport(viewport(x=unit(0.7,"npc"),y=unit(0,"npc"),width=0.4,height=0.95,name="vp1",just=c("left","bottom"))) grid.raster(barrel,width=unit(1,"npc"),just=c("centre","bottom"),x=unit(0.2,"npc"),y=unit(3,"line")) grid.text("Top Five Importing\nCountries of Crude Oil\nand Petrolium\nProducts in 2007\nfor the united States",x=unit(0.2,"npc"),y=unit(1,"npc")-unit(2,"line"),just=c("center","top")) savePlot("fig3_7.png")

Date: 2012-09-12 21:56:59 CEST

Author: mandy

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