[R] : plot different axis, same plot position
Pelt van, Saskia (KNMI)
saskia.van.pelt at knmi.nl
Wed Nov 17 18:19:42 CET 2010
Dear R-users,
I am trying to make a plot in R where x and y are plotted in a regular way, but the x axis corresponds to another set of values.
For example I have x,y and T (all 29 values)
x<- c( -1.31846232, -1.04744756, -0.87034853, -0.72883370, -0.60618971, -0.49501845, -0.39128988, -0.29250120, -0.19694055, -0.10334039, -0.01069355, 0.08185470, 0.17507665, 0.26971270, 0.36651292,
0.46627625, 0.56989300, 0.67839644, 0.79303127, 0.91535108, 1.04736522, 1.19177282, 1.35235778, 1.53470330, 1.74760041, 2.00616370, 2.33996397, 2.82073311, 3.72564504)
y<-c(51.85177, 53.67026, 60.64062, 62.33320, 62.81224, 63.20116,76.10719, 78.07620, 78.83859, 80.06188, 84.53568, 85.15358, 87.39279, 87.49965, 89.88347, 90.73792, 90.92971, 92.17759,
92.84064, 93.17964, 97.51360, 97.64690, 98.20756, 101.64150,104.91425, 112.88917, 116.90400, 121.50099, 126.43808)
T<- c(1.190283, 1.240506, 1.295154, 1.354839, 1.420290, 1.492386, 1.572193, 1.661017,
1.760479, 1.872611, 2.000000, 2.145985, 2.314961, 2.512821, 2.747664, 3.030928, 3.379310, 3.818182, 4.388060, 5.157895, 6.255319, 7.945946, 10.888889, 17.294118, 42.000000)
plot(x,y,xlab="x", ylab="10 day maximum (mm)",col="blue",type="b",pch=1,lty=2)
This plot is the correct plot, but I want the x-axis to display the values of T
If I do this:
plot(x,y,xlab="x", ylab="10 day maximum (mm)",xaxt="n", col="blue",type="b",pch=1,lty=2)
axis(1,las=0,T)
than the T is plotted in stead of x, but on the same scale. So the tickmarks start at 1 and stop at 3. I would like each point of the graph to correspond to a value of T on the x-axis, but the plot position should still correspond to x.
This means that y corresponds to the x values in plot position, but to the T value on the x-axis. I want this because the x values have no explanatory meaning (Gumbel variates), while the T values (return period) have, so I can use it to communicate what is happening in this graph.
I hope somebody can help me with this.
Kind regards,
Saskia van Pelt
More information about the R-help
mailing list