# [R] How to plot curves with more than 8 colors

Uwe Ligges ligges at statistik.uni-dortmund.de
Tue Dec 27 11:37:56 CET 2005

```Vincent Deng wrote:

> Dear Uwe,
>
> Sorry, I did not describe my question clearly. I created a matrix to
> store color code using rgb function.
>
> abc = rgb(6:36,0,0,maxColorValue = 255)
>
> And after running codes like this
>
> for (i in c(1:20))
> {
>    points(...,...,col=abc[i])
>    lines(...,col=abc[i])
> }
>
> R still used 8 colors of abc color codes repeatedly to draw the diagram
>
> Any helps?

No, it does not (in fact, all appears to be more or less black on my
screen ;-)). Another example:

plot(1:255, col=rgb(1:255,0,0,maxColorValue = 255))

Uwe Ligges

> Best Regards...
>
> On 12/27/05, Uwe Ligges <ligges at statistik.uni-dortmund.de> wrote:
>
>>Vincent Deng wrote:
>>
>>>Hi,
>>>
>>>I'm a new hand in R language. I have about 20 groups of data[x,y] and
>>>want to plot them on a graph. To do this, I write a for-loop as
>>>following: (some codes are omitted for simplicity)
>>>
>>>for (i in c(1:20))
>>>{
>>>  points(...,...,col=i)
>>>  lines(...,col=i)
>>>}
>>>
>>>The problem is "R only plot them with 8 colors repeatly". Could anyone
>>>help me solve this problem? Or is there any package providing plot
>>>function without color limit?
>>
>>
>>After typing
>>
>>  ?colors
>>
>>I get a nice help page that points me to a lot of other functions that
>>generate more than 8 colors. Maybe your installation of R is broken and
>>you cannot see this help page? You certainly tried to get help on colors
>>as well.
>>
>>There is no limit of the color number in the functions above, simply
>>specify the color you want to get. The only color limit applies for the
>>device and for most devices and rgb colors this is 256^3.
>>
>>Uwe Ligges
>>
>>
>>
>>
>>
>>>Best Regards...
>>>
>>>______________________________________________
>>>R-help at stat.math.ethz.ch mailing list
>>>https://stat.ethz.ch/mailman/listinfo/r-help