[R] Line Graph - Greater than 2 variables on plot

[Jim Lemon]

Wayne Aldo Gavioli wrote:
> 
> Hello all,
> 
> I was wondering if anyone knew how to construct a multiple line graph on R,
> where there are 2 (or more) sets of data points plotted against some x axis of
> data, and you can draw a line on the graph connecting each set of data points.
> 
> For example:
> 
> A               B              C          D
> 0.6566        2.1185        1.2320        5
> 0.647         2.0865        1.2325        10
> 0.6532        2.1060        1.2287        15
> 0.6487        2.1290        1.2313        20
> 0.6594        2.1285        1.2341        25
> 0.6577        2.1070        1.2343        30
> 0.6579        2.1345        1.2340        35
> 0.6734        2.1705        1.2362        40
> 0.675         2.1845        1.2372        45
> 0.6592        2.1550        1.2340        50
> 0.6647        2.1710        1.2305        55
> 
> 
> 
> Would there be a way:
> a) To graph all the points of data in sets A, B and C as Y coordinates on one
> graph, using the points in set D as the X-axis/coordinates for all 3 sets (A, B
> and C)?
> b) To be able to draw 3 lines on the graph that connect each set of data (1 line
> connects all the A points, one line connects all the B points, one line connects
> all the C points)
> 
> 
> I couldn't find anything in the examples or the help section about multiple
> lines on the same graph, only one line.
> 
Hi Wayne,

Assume your data is in a data frame named "wag":

plot(wag$D,wag$A,main="Three variable plot",xlab="D",ylab="Value",
  ylim=range(wag[c("A","B","C")]),type="l",col=2)
lines(wag$D,wag$B,type="l",pch=2,col=3)
lines(wag$D,wag$C,type="l",pch=3,col=4)
legend(25,1.9,c("A","B","C"),lty=1,col=2:4)

Jim