R help - Dec 2013 - Problem with R colors

Hello,

I am having difficulty obtaining the correct colors in my R charts.
> colors()[c(552, 254, 26)]
[1] "red"   "green" "blue"

But, if I specify col=552 in my barplot, I get gray bars.  Likewise,
col=254 gives bright pink, and col=26 is a red-orange.   I get accurate
results when I spell out the names, but I am making a pallet with 20- 30
colors and it is a real pain to have to do that.  Can anyone help me figure
out what I am doing wrong?

Thanks

	[[alternative HTML version deleted]]

Hi,

col=552 isn't the same as colors()[552] - I think the former is drawn
from your current palette, with recycling of indices. The default
color palette has only eight colors.

You need instead

col=colors()[552]

It's very difficult to get 20-30 readily distinguishable colors. You
might try the RColorBrewer package for smaller tasks, though.


Sarah


On Mon, Dec 9, 2013 at 5:12 PM, Katharine Miller <kmill117 at alaska.edu>
wrote:
> Hello,
>
> I am having difficulty obtaining the correct colors in my R charts.
>
>> colors()[c(552, 254, 26)]
> [1] "red"   "green" "blue"
>
> But, if I specify col=552 in my barplot, I get gray bars.  Likewise,
> col=254 gives bright pink, and col=26 is a red-orange.   I get accurate
> results when I spell out the names, but I am making a pallet with 20- 30
> colors and it is a real pain to have to do that.  Can anyone help me figure
> out what I am doing wrong?
>
> Thanks
-- 
Sarah Goslee
http://www.functionaldiversity.org

The full details on the col= argument can be found in the
section titled "Color Specification" on the help page for par -
?par.

Basically, col= accepts color names, hexadecimal RGB, or an
integer designating a position on the current palette. You can
get the current palette using
> palette()
[1] "black"   "red"     "green3"  "blue"
"cyan"    "magenta"
"yellow" 
[8] "gray" 

Any of these will give you red

col="red"
col="#FF0000"
col=2

You can change the palette colors with the palette() function,
but some graphics functions draw axes, text, etc assuming the
first color in the palette is black so it may be better to
create a vector of the colors you want, eg. 

mc <- colors()[c(552, 254, 26)]

and then use 

col=mc[1]

-------------------------------------
David L Carlson
Department of Anthropology
Texas A&M University
College Station, TX 77840-4352

-----Original Message-----
From: r-help-bounces at r-project.org
[mailto:r-help-bounces at r-project.org] On Behalf Of Katharine
Miller
Sent: Monday, December 9, 2013 4:12 PM
To: r-help at r-project.org
Subject: [R] Problem with R colors

Hello,

I am having difficulty obtaining the correct colors in my R
charts.
> colors()[c(552, 254, 26)]
[1] "red"   "green" "blue"

But, if I specify col=552 in my barplot, I get gray bars.
Likewise,
col=254 gives bright pink, and col=26 is a red-orange.   I get
accurate
results when I spell out the names, but I am making a pallet
with 20- 30
colors and it is a real pain to have to do that.  Can anyone
help me figure
out what I am doing wrong?

Thanks

	[[alternative HTML version deleted]]

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