Question

I am using a data set like:

1  48434  14566
1  56711  6289
1  58826  4174
2  56626  6374
2  58888  4112
2  59549  3451
2  60020  2980
2  60468  2532
3  56586  6414
3  58691  4309
3  59360  3640
3  59941  3059
.
.
.
10  56757  6243
10  58895  4105
10  59565  3435
10  60120  2880
10  60634  2366

I need a plot in R of 3rd column for each value of first column i.e. for above data there would be 10 different plots of (each group 1-10) of values of 3rd column. x-axis is number of Iterations and Y-axis is the values with max 63000. I also need to connect the dots with a line in color red.
I am new to R and have been reading documentation but that confused me more. could any body plz help.

EDIT: I actually want line graph of V3 values. the number of rows of v3 column would be on x-axis and v3 values on y-axis. And I want different graphs each for a group indicated by v1. Chase’s solution works except that I want the axis shifted, the V3 values should be on y-axis.here is example

EDIT2: @Roman, Here is the code I am executing.

library(lattice)
d <- read.delim("c:\\proj58\\positions23.txt",sep="")
d <- do.call(rbind, lapply(split(d, d$V1), function(x) {
    x$iterations <- order(x$V3, decreasing=TRUE)
    x
}))
xyplot(V3 ~ iterations | V1, type="l", data=d)

This is the error I get,

    > 
>  source("C:\\proj58\\plots2.R")
> d
       V1    V2    V3 iterations
1.1     1 48434 14566          1
1.2     1 56711  6289          2
1.3     1 58826  4174          3
1.4     1 59528  3472          4

I am not getting any plot?? what am I missing
OK: Got It. don’t know what was wrong. Here it is,

2 more things, how to change V1 labels on the boxes to actual numbers like 1,2,…
secondly I have files that contain 100 groups, I tried one and it made all graphs on a single page (unreadable obviously), can I make these on more than one windows?

Answer 1

Well, first you need to create a variable with the row number, for each subset of the first variable separately. Here’s one way to do it, by splitting the data set by the first variable, making a new variable that has the row number, and recombining.

You also probably want V1 to be a factor (a categorical variable).

d <- do.call(rbind, lapply(split(d, d$V1), function(x) {
    x$iterations <- 1:nrow(x)
    x
}))
d$V1 <- factor(d$V1)

Then using the lattice library, you’d do something like

xyplot(V3 ~ iterations | V1, type="l", data=d)

To make the plots appear on more than one page, limit the number of plots on a page using the layout option. You’ll need to save the plot to a file that supports multi-page output to do that. For example, for 5 rows and 5 columns:

trellis.device("pdf", file="myplot.pdf")
p <- xyplot(V3 ~ iterations | V1, type="l", data=d, layout=c(5,5))
plot(p)
dev.off()

Also, to make the plot appear when running the code using source, you need to specifically plot the output from the xyplot command, like

p <- xyplot(...)
plot(p)

When running at the console, this is not necessary as the plot (well, actually, the print function) is called on it by default.