R help - Nov 2009 - Is there a way to convert rgb/hex value to a (nearest) color name?

Hi all, I'm trying to convert a series of rgb codes into a color name.
What is my easiest option? So far I'm stuck with just converting to
hex using rgb() and I know R knows a number of colours() but a mapping
of the two has failed me.

Any help in this regard will be highly appreciated.

Regards,

George

Try this:
> mycolor <- col2rgb("red"); mycolor
      [,1]
red    255
green    0
blue     0
> colors()[sapply(lapply(colors(), col2rgb), identical, mycolor)]
[1] "red"  "red1"


On Mon, Nov 30, 2009 at 2:25 PM, Jorgy Porgee
<jorgy.porgee@gmail.com>wrote:
> Hi all, I'm trying to convert a series of rgb codes into a color name.
> What is my easiest option? So far I'm stuck with just converting to
> hex using rgb() and I know R knows a number of colours() but a mapping
> of the two has failed me.
>
> Any help in this regard will be highly appreciated.
>
> Regards,
>
> George
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
	[[alternative HTML version deleted]]

On 30/11/2009 2:25 PM, Jorgy Porgee wrote:
> Hi all, I'm trying to convert a series of rgb codes into a color name.
> What is my easiest option? So far I'm stuck with just converting to
> hex using rgb() and I know R knows a number of colours() but a mapping
> of the two has failed me.
>
> Any help in this regard will be highly appreciated.
>
>   
Here's a recent post on this by Barry Rowlingson:

http://finzi.psych.upenn.edu/Rhelp08/2009-October/214886.html

Duncan Murdoch

Fantastic. Thanks Duncan. Clearly my google key words were the wrong
ones, nothing of this sort came up. Hope my title is easier to find
somehow..

Regards,

George

You can try something about like this:

yourColor <-  c(250,235,215)
colors()[which.min(colSums(col2rgb(colors()) - yourColor
)[colSums(col2rgb(colors()) - yourColor) >= 0])]

On Mon, Nov 30, 2009 at 5:25 PM, Jorgy Porgee <jorgy.porgee at gmail.com>
wrote:
> Hi all, I'm trying to convert a series of rgb codes into a color name.
> What is my easiest option? So far I'm stuck with just converting to
> hex using rgb() and I know R knows a number of colours() but a mapping
> of the two has failed me.
>
> Any help in this regard will be highly appreciated.
>
> Regards,
>
> George
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>


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