[R] ggmap (or ggplot2 with mapping question)

[Roy Mendelssohn - NOAA Federal]

HI All:

Okay I am feeling particular brain dead today.  i have the following map created so far using ggmap:

> library(ggmap)
> myLocation <- c(-178, -28, -72, 48)
> myMap <- get_map(location=myLocation, source="google", maptype="satellite", crop=FALSE)
> 

I want to color in some lat-lon 5 degree boxes based on some criterion,  and it look like this could be done use geom_polygon if I can figure out how to get the data in the format required for geom_polygon.  To simplify the problem, suppose i have a bounding box:

subbox<-c(-130, 20, -125, 25)

and I want to color that box red on myMap defined above.    To put this in context, I actually have 360 squares which have been clustered by some criteria, and I want to color them all based on the cluster number of the box. but if I can figure out how to do the simple problem above I can  extend it to the more general problem.

Basically the question is how can I get that simple box information into the format required for geom_polygon.

Thanks for any help.

-Roy


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"The contents of this message do not reflect any position of the U.S. Government or NOAA."
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Roy Mendelssohn
Supervisory Operations Research Analyst
NOAA/NMFS
Environmental Research Division
Southwest Fisheries Science Center
***Note new address and phone***
110 Shaffer Road
Santa Cruz, CA 95060
Phone: (831)-420-3666
Fax: (831) 420-3980
e-mail: Roy.Mendelssohn at noaa.gov www: http://www.pfeg.noaa.gov/

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