Section 13 Base Graphics

• The original R graphics package is referred to as base graphics.

• Successive functions to add graphics and build plots up.

• Function: high-level \(\large \longrightarrow\) Create new graphs

• Function: low-level \(\large \longrightarrow\) Annotate plots

• Default graphics parameters can be altered to customise the plot

13.1 High Level Graphics

Function	Explanation
plot	Scatterplot
pairs	Scatterplot matrix
coplot	Conditioning plot
hist	Histogram
stem	Stem-and-leaf plot
boxplot	Box-and-whisker plot
qqnorm	Quantile-quantile plot
barplot	Bar plot
dotchart	Dot plot
interaction.plot	Profile plot of group means

13.2 Low Level Graphics

Function	Explanation
points	Plot points at given coordinates
lines	Draw lines between given coordinates
text	Draw text at given coordinates
mtext	Draw text in the margins of a plot
abline	Draw a line of given intercept and slope, or a horizontal and/or vertical line
axis	Add an axis
arrows	Draw arrows
segments	Draw line segments
rect	Draw rectangles
polygon	Draw polygons
box	Draw a box around the plot
grid	Add a rectangular grid
legend	Add a legend (a key)
title	Add labels

13.3 Graphics Parameters

• For detailed helps on graphics parameters: ?par

Function	Explanation
main	Title of the plot
ylab, xlab	Labels for the y-axis and x-axis
ylim, xlim	Limits for the y-axis and x-axis
type	Plot type (points, lines, both, …),
pch	Plot character (circles, dots, triangles, symbols, …)
cex	Character expansion (size of plot characters)
lty	Line type (solid, dots, dashes, …)
lwd	Line width
col	Colour of plot characters
las	Orientation of the text on the tick marks