[R] Use of different colours in plot

[Jim Lemon]

On Fri, 18 Jul 2014 07:07:04 AM Stefano Sofia wrote:
> Dear R list users,
> I have a data frame called catchment like
> 
> "year" "season" "rainfall" "colour"
> 1953 1 409.5 "black"
> 1953 2 145.3 "black"
> 1953 3 285.6 "red"
> 1953 4 275.0 "black"
> 1954 1 273.8 "black"
> 1954 2 342.8 "blue"
> 1954 3 167.6 "black"
> 1954 4 341.1 "black"
> 1955 1 182.3 "blue"
> 1955 2 211.8 "black"
> 1955 3 222.6 "black"
> 1955 4 522.1 "black"
> 1956 1 248.7 "red"
> 1956 2 244.9 "black"
> ...
> 
> and I would like to plot it with the colours specified in the column 
colour
> (at the moment the colours are three: black, red and blue. I would 
like to
> have the possibility to add oher colours to this list).
 With
> 
> plot(catchment$year, catchment$rainfall, main="River Aso", 
xlab="years",
> ylab="mm", type="p", col=catchment$colour)
 
> the colours displayed in the graph are not the ones I have chosen.
> I looked for the answer, which probably involves a transformation to 
factor,
> but I am not able to understand well the solution.
 Could somebody help me?
> 
> Thank you
> Stefano Sofia
> 
Hi Stefano,
Try this:

plot(catchment$year, catchment$rainfall,
 main="River Aso", xlab="years",
 ylab="mm", type="p",
 col=as.character(catchment$colour))

Jim