Re: [R] masking a regular lat/lon grid to extract map boundaries

2008-10-07 Thread Greg Snow
Intermountain Healthcare [EMAIL PROTECTED] 801.408.8111 > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > project.org] On Behalf Of claudia tebaldi > Sent: Tuesday, October 07, 2008 4:09 PM > To: r-help@r-project.org > Subject: [R] masking a regular lat/l

Re: [R] masking a regular lat/lon grid to extract map boundaries

2008-10-07 Thread Duncan Murdoch
On 07/10/2008 6:08 PM, claudia tebaldi wrote: Dear R-helpers, I have lat/lon coordinates of regularly spaced grid points, about 4Km apart, covering the entire US continental region. I would like to mask this rectangular grid in order to extract all and only the grid points within a specific regi

[R] masking a regular lat/lon grid to extract map boundaries

2008-10-07 Thread claudia tebaldi
Dear R-helpers, I have lat/lon coordinates of regularly spaced grid points, about 4Km apart, covering the entire US continental region. I would like to mask this rectangular grid in order to extract all and only the grid points within a specific region. Today I want to extract Montana, say, from