function [umask,vmask,pmask]=uvp_masks(rmask);

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Hernan G. Arango %%%%
%  Copyright (c) 2001 Rutgers University                               %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%                                                                      %
%  function [umask,vmask,pmask]=uvp_masks(rmask)                       %
%                                                                      %
%  This function computes the Land/Sea masks on U-, V-, and PSI-points %
%  from the mask on RHO-points.                                        %
%                                                                      %
%  On Input:                                                           %
%                                                                      %
%    rmask        Land/Sea mask on RHO-points (real matrix).           %
%                                                                      %
%  On Output:                                                          %
%                                                                      %
%    umask        Land/Sea mask on U-points (real matrix).             %
%    vmask        Land/Sea mask on V-points (real matrix).             %
%    pmask        Land/Sea mask on PSI-points (real matrix).           %
%                                                                      %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

[Lp,Mp]=size(rmask);
L=Lp-1;
M=Mp-1;

%  Land/Sea mask on U-points.

umask(1:L,1:Mp)=rmask(2:Lp,1:Mp).*rmask(1:L,1:Mp);

%  Land/Sea mask on V-points.

vmask(1:Lp,1:M)=rmask(1:Lp,2:Mp).*rmask(1:Lp,1:M);

%  Land/Sea mask on PSI-points.

pmask(1:L,1:M)=rmask(1:L,1:M ).*rmask(2:Lp,1:M ).* ...
               rmask(1:L,2:Mp).*rmask(2:Lp,2:Mp);

return