[R-sig-Geo] fix color scale

[Jim Lemon]

On 10/29/2010 06:12 AM, Peter Larson wrote:
> Hello!
>
> I have a problem.
>
> I am using IDW to interpolate a daily series of geospatial
> observations. Thus, I want to produce a large number of sequential
> maps.
>
> I want them to all represent the same color scale. Is there any way to
> fix the color scale so that it is the same for all the plots?
>
Hi Pete,
This can be done with the color.scale function by tacking the extreme 
values onto the actual ones for the scaling, then removing the extreme 
values when plotting. See the second example for the barp function in 
the plotrix package. This may work for other value to color 
transformation functions as well.

Jim