Re: [R] Spatial sampling problem

2007-08-07 Thread Julian Burgos
Hello SK,

I suggest you try the RandomFields package.  It has specific functions 
for simulating random fields with an array of different algorithms and 
distributions.  The GaussRF function in particular normal generates 
random fields.

Julian

Julian M. Burgos

Fisheries Acoustics Research Lab
School of Aquatic and Fishery Science
University of Washington

1122 NE Boat Street
Seattle, WA  98105 

Phone: 206-221-6864


sk wrote:
 Hi All,
   I am new in R and trying to simulate random normal 2D field with mean trend 
 say north-south. My domain is 10x10 grid and I am trying to use mvnorm but do 
 not know how to specify the domain and the mean field. 
   I would appreciate any help.
   Cheers, SK  


 -


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[R] Spatial sampling problem

2007-08-06 Thread sk
Hi All,
  I am new in R and trying to simulate random normal 2D field with mean trend 
say north-south. My domain is 10x10 grid and I am trying to use mvnorm but do 
not know how to specify the domain and the mean field. 
  I would appreciate any help.
  Cheers, SK  

   
-


[[alternative HTML version deleted]]

__
R-help@stat.math.ethz.ch 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.


Re: [R] Spatial sampling problem

2007-08-06 Thread Moshe Olshansky
Hi SK,

If I understand you correctly you are trying to assign
to each point of a 10x10 2D grid a normal variable
with a certain dependency between the values at each
grid point. Is this correct?
If so, please explain the dependence structure. Do you
need something like X(i,j) = f(i,j) + Z(i,j) for
1=i,j=10 where f is a deterministic function and
Z(i,j) are independent normal variables? Or do you
want to assume that Z(i,j) have a multivariate normal
distribution (and can specify the covariance matrix)?

Regards,

Moshe.

--- sk [EMAIL PROTECTED] wrote:

 Hi All,
   I am new in R and trying to simulate random normal
 2D field with mean trend say north-south. My domain
 is 10x10 grid and I am trying to use mvnorm but do
 not know how to specify the domain and the mean
 field. 
   I would appreciate any help.
   Cheers, SK  
 

 -
 
 
   [[alternative HTML version deleted]]
 
 __
 R-help@stat.math.ethz.ch 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.


__
R-help@stat.math.ethz.ch 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.