R- Plot graph with certain variable

Question

This is what my dataframe looks like:

    Persnr    Date    AmountHolidays
1   55312     X201101 2
2   55312     X201102 4.5
3   55312     X201103 5
etc.

What I want to have is a graph that shows the amount of holidays (on the y-axis) of each period (Date on the x-axis) of a specific person (persnr). Basically, it's a pivot graph in R. So far I know, it is not possible to create such a graph. Something like this is my desired result:

http://imgur.com/62VsYdJ

Is it possible in the first place to create such a model in R? If not, what is the best way for me to visualise such graph in R? Thanks in advance.

Answer 1

You can try with package ggplot2:

First option

ggplot(dat, aes(x=Date, y=AmountHolidays, group=Persnr)) + 
 geom_line(aes(colour=Persnr)) + scale_colour_discrete()

or

Second option

ggplot(dat, aes(x=Date, y=AmountHolidays, group=Persnr)) + 
 geom_line() + facet_grid(~Persnr)

One of the advantages is that you don't need to have a line per Persnr or even to specify (to know) the name or number of Persnr.

example:

first option second option

Data:

dat <- structure(list(Persnr = structure(c(1L, 1L, 1L, 2L, 2L, 2L), .Label = c("54000", 
"55312"), class = "factor"), Date = structure(c(1L, 2L, 3L, 1L, 
2L, 3L), .Label = c("2011-01-01", "2011-02-01", "2011-03-01"), class = "factor"), 
    AmountHolidays = c(5, 4.5, 2, 3, 6, 7)), .Names = c("Persnr", 
"Date", "AmountHolidays"), row.names = c(3L, 5L, 6L, 1L, 2L, 
4L), class = "data.frame")

Answer 2

Something like this could do the trick?

dat <- read.table(text="Persnr    Date    AmountHolidays
55312     2011-01-01 2
55312     2011-02-01 4.5
55312     2011-03-01 5
55313     2011-01-01 4
55313     2011-02-01 2.5
55313     2011-03-01 6", header=TRUE)

dat$Date <- as.POSIXct(dat$Date)
dat$Persnr <- as.factor(dat$Persnr)

# Build a primary graph
plot(AmountHolidays ~ Date, data = dat[dat$Persnr==55312,], type="l", col="red",
     xlim = c(1293858000, 1299301200), ylim=c(0,8))

# Add additional lines to it
lines(AmountHolidays ~ Date, data = dat[dat$Persnr==55313,], type="l", col="blue")

# Build and place a legend
legend(x=as.POSIXct("2011-02-19"), y=2.2, legend = levels(dat$Persnr),fill = c("red", "blue"))

To set X coordinates, you can either use as.POSIXct(YYYY-MM-DD) or as.numeric(as.POSIXct(YYYY-MM-DD) as I did for the xlim's.